Database Develop

[Q] Need Help: Using In Japan

Hello. I posted this yesterday in the Nexus S forum (I have an S, not a One) but no one seems to know the answer so I was wondering if perhaps someone here could help out, as the Nexus One has been out for some time now.
In a nutshell, I would like to know how in the world I can get my unlocked Nexus S to work in Japan with respect to data transmission.
Early this year I developed an interest in foreign smartphones as all we had here in Japan was the (IMHO) horrid Xperia X10 and the wonderful HTC Desire. I have purchased a number of phones from overseas (either Hong Kong or the UK) including:
HTC Mini (HK)
HTC Desire (HK)
Xperia X2 (UK)
Galaxy S (UK)
Galaxy Tab (UK)
Nexus S (USA)
Now here's the thing: ALL of these phones were unlocked yet NONE of them allowed any data transmission except the HTC Mini. To this day I fail to understand why.
When I got the HTC Mini, I was using the Mopera U APN/service. I put my Docomo SIM card into the Mini and without doing anything at all, it had data connectivity from the start. To this day I question if it was something related to Windows Mobile, as all of the other phones I listed above are Android (except for the X2).
I had Mopera U with all of these other phones and yet NONE of them work, even after I have tried multiple APN services and have manually typed in the APN settings (i.e. mpr2.bizho.net, spmode.ne.jp, mopera.flat.foma.ne.jp, etc).
Just yesterday I received my unlocked Nexus S from the USA and while it hardly came as a surprise, I am nonetheless infuriated once again that the phone refuses to connect to the wireless network.
It should be noted however that the very first time I attempted to connect the Nexus S to the mpr2.bizho.net APN, for a scant one second, the 3G data transmission icon appeared in the taskbar at the top of the screen, but then immediately disappeared. Since that initial setting, it has never reappeared when I toggle the APN.
Can anyone please offer some advice here? I fail to believe that there is absolutely no way to use this phone in Japan. With all the different network bands and whatnot supported by this phone, surely it has to work. I am still at a loss as to why the Galaxy S and Galaxy Tab failed to connect to the network here when both are in fact, available for purchase domestically. Are the manufacturers actually creating modified band phones for each country despite making the same exact product?
Docomo is absolutely no help whatsoever, claiming that the ONLY band supported here is "3G" and denying any understanding of the other band spectrums (i.e. Quad Band GSM, Tri-Band HSPA, etc).
Some of the IT-related people I know have suggested that my phone is in fact, NOT unlocked and thus the problem stems from that, however considering that the phone will instantly register the NTT DOCOMO network and I can make calls and receive SMS messages, I fail to believe the phone is locked.
I will bring up a point that a friend passed onto me: They suggested that perhaps my problem is that the phone won't work because the previous carrier settings are still on it. The seller on eBay however stated that this was a factory unlocked phone and thus I don't think this applies, though I was a bit confused as to why there was a T-Mobile SIM card inside the Nexus S box, which led me to believe that perhaps the phone is unlocked but it is "defaulted" to T-Mobile network values?
Anyway if anyone could be of some assistance here I would greatly appreciate it.

You seem to know your stuff -- so I'm baffled as to why this isn't working for you.
You're armed with the Docomo APN and authentication, as well as compatible hardware. NTT Docomo (as well as SoftBank) operate 3G/UMTS/HSDPA on 2100Mhz, which your Nexus S supports.
Each year I visit family, I get a rental SIM, get the spiel that loaner SIMs aren't allowed to be used in smartphones (might have changed now). So they give me a phone instead, which I just rip the SIM out of and place in my phone.
I doubt your previous carriers' info would be interfering, since I'm guessing the only entry you have under operators is Docomo (and removed every other carrier), and you have your FOMA SIM inserted.
The only thing I can think of are: your HTC Mini's passing some authentication type handshake (or maybe it's a parameter or setting its' flipping), or the network has some strange blanket ban on IMEI numbers.
Both scenarios are pretty unlikely -- which brings me back to me being baffled. I was able to rip out a SIM and use in a Nokia E51 and an HP iPaq 910 (a handset not sold in Japan). I just entered in some APN settings and it was happy as pigs in ****.
I'm sorry I don't have anything more to offer -- but from what you said, and you are correct -- this should work.
This might sound obvious : Sometimes, Android will have a database built in with APN settings and will use those. Sometimes, It'll read the settings off of the SIM, and use those. Some cases, the auto-selected values might be incorrect if the carrier changed something on their end. Or sometimes, it might not do anything at all. You might have already tried this -- find a working handset (HTC Mini, friend, demo unit in a store, etc), write the settings down and enter them in by hand on your Nexus S. If you've already tried this, I apologize.

GrapeneOS Compatibility?

Hello,
Does anyone know if there are versions of the Google Pixel 5 that have locked bootloaders? For example on the Galaxy S10e Snapdragon model you can't enable OEM unlocking with a certain bootloader version, however on the Exynos version this isn't as much of an issue. Are there specific updates on the Google Pixel that may prevent you from using GrapheneOS? If I get a Google Pixel I want to ensure it will be compatible with GrapheneOS.
Thanks!

Verizon is locked. Keep away from Verizon variants for basically any device if you want it to have bootloader unlocking. AT&T also I believe. Unlocked variant is usually the way to go.

andybones said:
Verizon is locked. Keep away from Verizon variants for basically any device if you want it to have bootloader unlocking. AT&T also I believe. Unlocked variant is usually the way to go.
Click to expand...
Click to collapse
I'm assuming you're American? I don't live in the USA so that shouldn't be a problem. If I go to a carrier in my country I'll see if they will let me handle the phone before buying it. I'd check to see if the OEM can be unlocked. Is there anything I should test or look at on the phone to determine compatibility?

Skyty said:
I'm assuming you're American? I don't live in the USA so that shouldn't be a problem. If I go to a carrier in my country I'll see if they will let me handle the phone before buying it. I'd check to see if the OEM can be unlocked. Is there anything I should test or look at on the phone to determine compatibility?
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Click to collapse
I am, sadly.
May I ask why not just buy the unlocked variant? I use it here in the US, and it seems to not be hardware specific. When I bought the Pixel 5 I was on Verizon, and switched recently to AT&T, and all it took was swapping of the sim card and all is working fine.
Are other carriers cheaper?
And If I am understanding correctly, as long as you can get into those dev settings and verify "OEM unlocking" is there and working, you are set. But, don't fall back on just my limited knowledge, as I don't really know outside the US, and as far as Pixels are concerned, once its bootloader is unlocked, nothing will be locking it down, like on Samsung. Sans strange cases like paying to unlock the bootloader of a locked down carrier variant, which I haven't come across on the Pixel 5.

andybones said:
I am, sadly.
May I ask why not just buy the unlocked variant? I use it here in the US, and it seems to not be hardware specific. When I bought the Pixel 5 I was on Verizon, and switched recently to AT&T, and all it took was swapping of the sim card and all is working fine.
Are other carriers cheaper?
And If I am understanding correctly, as long as you can get into those dev settings and verify "OEM unlocking" is there and working, you are set. But, don't fall back on just my limited knowledge, as I don't really know outside the US, and as far as Pixels are concerned, once its bootloader is unlocked, nothing will be locking it down, like on Samsung. Sans strange cases like paying to unlock the bootloader of a locked down carrier variant, which I haven't come across on the Pixel 5.
Click to expand...
Click to collapse
And here we come full circle once again. The problem is that unlocked does not mean bootloader unlockable which I know you know but others might not. GrapheneOS needs to have an unlocked bootloader or it will not install. I don't know how a buyer can get a business to boot into the OS in order to see if the OEM switch is active. But as you state that is really the only way to tell. @Skyty which carrier are you using? I don't know how you will get that guarantee that you can unlock the bootloader but that is really what you need to do if you can't handle the phone.

In the case of Pixels, the unlocked version has the added bonus of having an unlockable bootloader, Google doesn't seem to play the games that Samsung does. They're both carrier unlocked and don't have the bootloader super locked down.

andybones said:
Verizon is locked. Keep away from Verizon variants for basically any device if you want it to have bootloader unlocking. AT&T also I believe. Unlocked variant is usually the way to go.
Click to expand...
Click to collapse
People that say "don't buy the Verizon model" never tell you that the unlocked Google version of the pixels brought to the Verizon network will NOT be VoLTE and preferred/default wifi calling options. There is NO root solution to this limitation that works.

Schroeder09 said:
People that say "don't buy the Verizon model" never tell you that the unlocked Google version of the pixels brought to the Verizon network will NOT be VoLTE and preferred/default wifi calling options. There is NO root solution to this limitation that works.
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Click to collapse
Correct me if I'm wrong but in my post I did say "usually" the way to go.
And, just to state, I had no issues with VoLTE on my rooted, unlocked variant P5 on Verizon, nor At&T, VoWIFI works also.. what am I doing special? Just curious. Here I am on a call using VoLTE.

Also, if they are creating VoLTE Magisk modules for China and more. This is the first complaint I've read about this issue. My HTC 10 was also an unlocked variant on Verizon with VoLTE, Wi-Fi Calling and preferred options were the same as my brother stock un-rooted Verizon variant. So, I'm lost. Sorry.

Schroeder09 said:
People that say "don't buy the Verizon model" never tell you that the unlocked Google version of the pixels brought to the Verizon network will NOT be VoLTE and preferred/default wifi calling options. There is NO root solution to this limitation that works.
Click to expand...
Click to collapse
Can you please explain this statement? I don't use wifi calling but I'm willing to test out your theories. I have an unlocked Google P5 and I'm on the Verizon network.

bobby janow said:
Can you please explain this statement? I don't use wifi calling but I'm willing to test out your theories. I have an unlocked Google P5 and I'm on the Verizon network.
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When you buy the Google bootloader unlocked phones and being them to Verizon they do NOT have all the locked down Verizon version phone capabilities. On a pixel with a locked bootloader purchased from vzw you will have options in your settings to enable VoLTE services AND to enable Wi-Fi calling by default meaning whenever you're on wifi the phone will default to making calls over wifi as opposed to a network. This is useful of you have poor reception in your house or place of work.
Without it the phone will only use wifi to make calls when the network is very, very poor, and it still will only use wifi sporadically. It will switch to the wifi network AFTER the call starts sometimes. This will cause momentary dead air where you miss words and may think you dropped the call. It's a total PITA. There are supposed fixes and options you can toggle in the phone app by dialing some crazy number which is actually a code to access options and settings in the phone app. None of these options work. There are 3 guys in the world who have had success with these options and work arounds, and I'm sure they'll chime in here to encourage you to spend $1200 on a p6 or $600+ on a p5 because you'll **probably** be able to get these functions working. If you need or greatly prefer VoLTE and/or wifi calling know that you probably will NOT be the 4th guy in history to have success with these work arounds.
I do not care about VoLTE at all. I have never had it, but I guess it's super clear voice AND it's only available in a (growing) list of big cities. Who cares about SUPER clear voice? How often do you even actually use your phone anyway? I DO care about preferred wifi calling as this has a definable, useful function, and I was and still am (4 years later) ticked about not having the ability to have my phone preferably select a wifi network regardless of the signal coming from the cell network.

Schroeder09 said:
When you buy the Google bootloader unlocked phones and being them to Verizon they do NOT have all the locked down Verizon version phone capabilities. On a pixel with a locked bootloader purchased from vzw you will have options in your settings to enable VoLTE services AND to enable Wi-Fi calling by default meaning whenever you're on wifi the phone will default to making calls over wifi as opposed to a network. This is useful of you have poor reception in your house or place of work.
Without it the phone will only use wifi to make calls when the network is very, very poor, and it still will only use wifi sporadically. It will switch to the wifi network AFTER the call starts sometimes. This will cause momentary dead air where you miss words and may think you dropped the call. It's a total PITA. There are supposed fixes and options you can toggle in the phone app by dialing some crazy number which is actually a code to access options and settings in the phone app. None of these options work. There are 3 guys in the world who have had success with these options and work arounds, and I'm sure they'll chime in here to encourage you to spend $1200 on a p6 or $600+ on a p5 because you'll **probably** be able to get these functions working. If you need or greatly prefer VoLTE and/or wifi calling know that you probably will NOT be the 4th guy in history to have success with these work arounds.
I do not care about VoLTE at all. I have never had it, but I guess it's super clear voice AND it's only available in a (growing) list of big cities. Who cares about SUPER clear voice? How often do you even actually use your phone anyway? I DO care about preferred wifi calling as this has a definable, useful function, and I was and still am (4 years later) ticked about not having the ability to have my phone preferably select a wifi network regardless of the signal coming from the cell network.
Click to expand...
Click to collapse
I've read this about 5 times already and I still have no idea what you are talking about. I don't really use wifi calling but I'd be willing to test your theory. Walk me through the steps and tell me what I'm looking for. Wait maybe the 6th time is the charm. So if I turn on wifi calling on my phone now in a very good network setting you are saying that it will not use wifi until the network drops out right? How can I test that?

bobby janow said:
I've read this about 5 times already and I still have no idea what you are talking about. I don't really use wifi calling but I'd be willing to test your theory. Walk me through the steps and tell me what I'm looking for. Wait maybe the 6th time is the charm. So if I turn on wifi calling on my phone now in a very good network setting you are saying that it will not use wifi until the network drops out right? How can I test that?
Click to expand...
Click to collapse
Don't bother man, I give ample proof.
The "dialing some crazy number which is actually a code to access options and settings in the phone app" is *#*#4636#*#* FWIW. That's where my 3-4 pictures come from.
He doesn't even use his phone as a phone, but is upset about WIFI calling, so once again, I'm lost, but I won't be replying to anything he has to say. and let's just leave it alone because I don't make fake posts, and don't want to keep going off-topic, for IMO, no reason.
Schroeder09 said:
When you buy the Google bootloader unlocked phones and being them to Verizon they do NOT have all the locked down Verizon version phone capabilities. On a pixel with a locked bootloader purchased from vzw you will have options in your settings to enable VoLTE services AND to enable Wi-Fi calling by default meaning whenever you're on wifi the phone will default to making calls over wifi as opposed to a network. This is useful of you have poor reception in your house or place of work.
Without it the phone will only use wifi to make calls when the network is very, very poor, and it still will only use wifi sporadically. It will switch to the wifi network AFTER the call starts sometimes. This will cause momentary dead air where you miss words and may think you dropped the call. It's a total PITA. There are supposed fixes and options you can toggle in the phone app by dialing some crazy number which is actually a code to access options and settings in the phone app. None of these options work. There are 3 guys in the world who have had success with these options and work arounds, and I'm sure they'll chime in here to encourage you to spend $1200 on a p6 or $600+ on a p5 because you'll **probably** be able to get these functions working. If you need or greatly prefer VoLTE and/or wifi calling know that you probably will NOT be the 4th guy in history to have success with these work arounds.
I do not care about VoLTE at all. I have never had it, but I guess it's super clear voice AND it's only available in a (growing) list of big cities. Who cares about SUPER clear voice? How often do you even actually use your phone anyway? I DO care about preferred wifi calling as this has a definable, useful function, and I was and still am (4 years later) ticked about not having the ability to have my phone preferably select a wifi network regardless of the signal coming from the cell network.
Click to expand...
Click to collapse
I don't know about you, but I USE my phone primarily as a phone., this is why own a tablet and a small 13" laptop.
And just because I do use my phone and you don't doesn't mean anything, as far as what others use theirs for, you're not to say and neither am I.
I'm up here in the boondocks with hardly ANY service on the weekends, and get crystal clear calling when I am connected to and with Wi-Fi Calling on.
No work-arounds for me, just an unlocked variant P5, rooted and on the stock ROM, now on AT&T, switched the other week.. And all I had to do was swap the SIM cards..
The only thing I suppose I can't fully check (that I'm aware of) is the "SUPER clear voice" preferred calling as IDK if it has a setting to turn on/off such as VoLTE/VoWIFI.
And even so, it's subjective to the person using and listening to the phone.
And I've been using an unlocked variant device on Verizon with "IMS, advanced calling, Wi-Fi calling and all other Verizon features" since the HTC 10!
So, just saying, this isn't exactly new. And I'm certainly not telling anyone to go out and buy anything just because I get these features.
And Bravo to these "3" people. IF they have it working and you don't, it is what it is, I guess, I don't know what to say, other than they aren't breaking any rules by posting about it.
Also, anyone who spends $600-1200 based off someone's single post.. That's on them, bro. You can't control how people spend their $$
And I'm certainly not making this post to try and shill anyone to buy an unlocked variant. Like you don't care about VoLTE, I don't care what phone someone buys.
I think these screenshots speak for themselves.

andybones said:
Don't bother man, I give ample proof.
The "dialing some crazy number which is actually a code to access options and settings in the phone app" is *#*#4636#*#* FWIW. That's where my 3-4 pictures come from.
He doesn't even use his phone as a phone, but is upset about WIFI calling, so once again, I'm lost, but I won't be replying to anything he has to say. and let's just leave it alone because I don't make fake posts, and don't want to keep going off-topic, for IMO, no reason.
I don't know about you, but I USE my phone primarily as a phone., this is why own a tablet and a small 13" laptop.
And just because I do use my phone and you don't doesn't mean anything, as far as what others use theirs for, you're not to say and neither am I.
I'm up here in the boondocks with hardly ANY service on the weekends, and get crystal clear calling when I am connected to and with Wi-Fi Calling on.
No work-arounds for me, just an unlocked variant P5, rooted and on the stock ROM, now on AT&T, switched the other week.. And all I had to do was swap the SIM cards..
The only thing I suppose I can't fully check (that I'm aware of) is the "SUPER clear voice" preferred calling as IDK if it has a setting to turn on/off such as VoLTE/VoWIFI.
And even so, it's subjective to the person using and listening to the phone.
And I've been using an unlocked variant device on Verizon with "IMS, advanced calling, Wi-Fi calling and all other Verizon features" since the HTC 10!
So, just saying, this isn't exactly new. And I'm certainly not telling anyone to go out and buy anything just because I get these features.
And Bravo to these "3" people. IF they have it working and you don't, it is what it is, I guess, I don't know what to say, other than they aren't breaking any rules by posting about it.
Also, anyone who spends $600-1200 based off someone's single post.. That's on them, bro. You can't control how people spend their $$
And I'm certainly not making this post to try and shill anyone to buy an unlocked variant. Like you don't care about VoLTE, I don't care what phone someone buys.
I think these screenshots speak for themselves.
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Click to collapse
^^^ one of the 3 people who gets this stuff to work.
My point to the question was that this stuff seldom works. No one knows why. It worked for you. Cool. You got lucky. There are plenty of us who never get it work with alllll the root options and magisk modules put there.

Schroeder09 said:
^^^ one of the 3 people who gets this stuff to work.
My point to the question was that this stuff seldom works. No one knows why. It worked for you. Cool. You got lucky. There are plenty of us who never get it work with alllll the root options and magisk modules put there.
Click to expand...
Click to collapse
No, I'm not that lucky, believe you me.
And I've let this go on long enough.
Anymore OT on this subject gets deleted.
Thank you.

I sell pixel devices basically for a living that have Graphene/Calyx on them. If its a carrier device and sitll locked to that carrier, the bootloader OEM Unlock option will be forever grayed out until the device is SIM Unlocked.
The Pixel 5 can be Unlocked, Verizon or ATT. ATT and VZW will be locked until sim unlocked

KaptinBoxxi said:
I sell pixel devices basically for a living that have Graphene/Calyx on them. If its a carrier device and sitll locked to that carrier, the bootloader OEM Unlock option will be forever grayed out until the device is SIM Unlocked.
The Pixel 5 can be Unlocked, Verizon or ATT. ATT and VZW will be locked until sim unlocked
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Click to collapse
I saw those phones being sold for double the list price of a P5. Is that true? So basically charging a few hundred dollars to install a rom / os that anyone with a semblance of knowledge can do themselves. I'm not sure I have the details correctly so let me know if I'm wrong.
As for the second part of your statement, the VZW P5 cannot be bl unlocked no matter what you do, sim lock or not. I'm not sure about ATT.

bobby janow said:
I saw those phones being sold for double the list price of a P5. Is that true? So basically charging a few hundred dollars to install a rom / os that anyone with a semblance of knowledge can do themselves. I'm not sure I have the details correctly so let me know if I'm wrong.
As for the second part of your statement, the VZW P5 cannot be bl unlocked no matter what you do, sim lock or not. I'm not sure about ATT.
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Click to collapse
I usually add +40 to +75, unless I have original boxes and accessories. They really do sell for more, and people pay it.
As for the VZW P5, I have a few in my shop office right now that cannot be unlocked and their IMEI reads back as a Verizon phone, double checked by inserting another SIM and comes up locked. VZW Statement on unlocking is "if the phone was paid off (6 months of payments), it will auto unlock" .. so you probably have one that's paid off.

No, I bought the Google version. Even paid up you can't unlock the Verizon version. It's just the way they operate.
Seems like a fair price. This is the article I was talking about. https://9to5google.com/2021/09/05/n...-focused-grapheneos-that-costs-twice-as-much/

Samsung Galaxy S10 - Unlocked Phone (AT&T Blocked Call Issue)

So many people are reporting with the 3/1 sweep by AT&T, that they are blocking almost all Unlocked phones: See: Downdector Link We personally have a S10 (G973U1). AT&T is saying on this list: AT&T approved phone list that it is supposed to work. But like many other people "calls" end immediately, but we can text and data work. It is some sorta ploy by AT&T to force us to upgrade our phones. They want us all to upgrade to S22s. Anyway I was ranting. Anyway, if you look at that link, they are saying that the phone has to be on the latest software. The last update from AT&T or the manufacturer was in January. I checked the firmware site, and Android 11 is the latest in January. I'm wondering if there is some hack to get us on to '12' or something. An update might solve this issue. We know that a new SIM does not work. Calls seem to be rejected on the network, just based on the phone model or Android version.
We are aware that a version 12 is out there for the phone, just that firmware is not for our US-unlocked model yet. But maybe it can be hacked?
Edit: It appears this thread may be linked with this older one... But it is ever more pressing issue now:
S10 Unlocked phone with AT&T Firmware here they explain how, and the problems with flashing. This was back in 2019, so I'm not sure if this will still work. Even then it didn't work for everyone. Some in that forum claimed that it did. AT&T seems to now be blocking from their calling network any phones not enabled with VOLTE and the extended AT&T services that are not present in Unlocked phones.

robertkjr3d said:
So many people are reporting with the 3/1 sweep by AT&T, that they are blocking almost all Unlocked phones: See: Downdector Link We personally have a S10 (G973U1). AT&T is saying on this list: AT&T approved phone list that it is supposed to work. But like many other people "calls" end immediately, but we can text and data work. It is some sorta ploy by AT&T to force us to upgrade our phones. They want us all to upgrade to S22s. Anyway I was ranting. Anyway, if you look at that link, they are saying that the phone has to be on the latest software. The last update from AT&T or the manufacturer was in January. I checked the firmware site, and Android 11 is the latest in January. I'm wondering if there is some hack to get us on to '12' or something. An update might solve this issue. We know that a new SIM does not work. Calls seem to be rejected on the network, just based on the phone model or Android version.
We are aware that a version 12 is out there for the phone, just that firmware is not for our US-unlocked model yet. But maybe it can be hacked?
Edit: It appears this thread may be linked with this older one... But it is ever more pressing issue now:
S10 Unlocked phone with AT&T Firmware here they explain how, and the problems with flashing. This was back in 2019, so I'm not sure if this will still work. Even then it didn't work for everyone. Some in that forum claimed that it did. AT&T seems to now be blocking from their calling network any phones not enabled with VOLTE and the extended AT&T services that are not present in Unlocked phones.
Click to expand...
Click to collapse
I was helped by a user to achieve ascendance onto the AT&T network. I'm not sure if I'm to reveal his name. We 1) go into Developers mode on the phone. 2) Hack the Kernel. 3) Flash the rom to the G973U (model)... with the AT&T firmware. So that the Wifi-Calling and 5G features would work, and AT&T would allow it on their network.

robertkjr3d said:
I was helped by a user to achieve ascendance onto the AT&T network. I'm not sure if I'm to reveal his name. We 1) go into Developers mode on the phone. 2) Hack the Kernel. 3) Flash the rom to the G973U (model)... with the AT&T firmware. So that the Wifi-Calling and 5G features would work, and AT&T would allow it on their network.
Click to expand...
Click to collapse
I've literally been searching for an answer to this for days now. My wife and I have S10's. I work far from home so I really need her phone working in case of emergency. Can you please point me in the general direction? Thanks!

Agreed, I didn't know such a thing was possible, but I'd love to hear more about this!

skrapmetal said:
I've literally been searching for an answer to this for days now. My wife and I have S10's. I work far from home so I really need her phone working in case of emergency. Can you please point me in the general direction? Thanks!
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Click to collapse
At first I had to use the Samsung Band Selector app from the Play store and go into More Network Settings > AT&T > Preferred Network Type and choose 3G. Unfortunately this killed LTE so all data and calls were going through H+. As I was mostly on wifi I could live with it since I could actually use the phone again.
Then Friday morning I checked for updates and there was the update to take me to Android 12. I took the update then when it finished it said it needed to reboot to connect new SIM to carrier services....it wasn't a new SIM. I let it reboot and everything was working with VoLTE again.
Hope this helps.

KennyG123 said:
At first I had to use the Samsung Band Selector app from the Play store and go into More Network Settings > AT&T > Preferred Network Type and choose 3G. Unfortunately this killed LTE so all data and calls were going through H+. As I was mostly on wifi I could live with it since I could actually use the phone again.
Then Friday morning I checked for updates and there was the update to take me to Android 12. I took the update then when it finished it said it needed to reboot to connect new SIM to carrier services....it wasn't a new SIM. I let it reboot and everything was working with VoLTE again.
Hope this helps.
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Click to collapse
I appreciate you getting back to me. Unfortunately I am still on android 11 with a custom ROM and also this is a global phone so that app didnt work for me. I dont receive OTA updatez. I'll update to a new ROM and see what happens. Thanks

SM-G973U VoLTE

I recently bought an unlocked Galaxy S10 SM-G973U on Amazon. Got new SIM card from a Verizon MVNO and activated phone. The phone downloaded Android 12, One UI version 4.0. Firmware Build number SP1A210812.016.G973USQS6HVA1. Service provide Software version SAOMC_SM-G973U_OYN_SPR_12_0007 SPR/XAA/VZW. The problem is there is no menu option to activate/switch on VoLTE which means when I'm on a call there is no internet. I've talked to the MVNO tech support multiple times and was told they couldn't see any problems on their side, or that the SM-G973U does not support VoLTE which is not true. I found on one of AT&T's sites that the SM-G973U needs a software patch to enable VoLTE. I also found a couple of USSD codes but they either didn't work or didn't get me to the right setup screen to turn on VoLTE. I even stopped by a Samsung store and they weren't any help either. They said they could re-flash a stock firmware but it would revert to being locked to a carrier which is apparently also not true based on what I've read on this forum. Anyone know how I can turn on VoLTE or know of an apk file or software patch to enable VoLTE?? Does one of the firmware versions posted online have the patch to turn on VoLTE??

I think the issue is that your phone is showing SPR/XAA/VZW. You say you're on a verizon MVNO (who, by the way?)... but your phone isn't seeing that. It's actually saying it's active for SPRint. The second one, XAA, means it's not able to detect the SIM type... and the third was that it was originally VZW, which you can't change and isn't really relevant. (That's just what the phone was "born" as).
Bottom line, your phone isn't seeing VZW or an MVNO as the active CSC nor the SIM card. In the past, the easy thing was to change the CSC to what you need, but I haven't found a way to do that actively. What's supposed to happen is that the CSC should update based on the SIM card and cell signal you're getting... but this doesn't always happen. I bought two phones - one switched with no issues, the other I could not get it to change no matter what I tried.
That said, the easiest thing is to clean flash the phone with ODIN to a VZW or your MVNO's ROM, so that (hopefully) the CSC updates automatically. You could also consider flashing a U1 (unlocked) ROM, as yours is not technically an unlocked ROM (U means it's a carrier ROM... which may be why it's not switching over?)
Again, I tried all of these on the second phone I bought, and nothing would switch it (my carrier is Total Wireless, which is a VZ MVNO, and actually shows up as Tracfone (TFN). I had to return that second phone and get another with TFN already activated, and that worked fine... so be sure you do this before you drop out of your return period.
Bottom line, you should be able to get this all working... my VOLTE/VOWIFI works fine... just a matter of getting you there.

Thanks. My carrier is Straight Talk which is now VZ. The SIM card they sent me has the wording "Verizon Compatible" written on it. I finally found a document that explains how to interpret the CSC codes and your explanation clarifies my understanding of it. Sound like I'll have to re-flash it. Since it was originally a VZW phone I'm thinking I should flash it back to VZW to see if that works before trying U1.

Dumb question as this is my first time flashing a phone. (I've flashed quite a few other things but never had to worry about CSC codes and bootloader versions, etc.) I don't see VZW firmware on samfirms or sammobile. I see Sprint, T-Mobile, and one listed as USA without carrier info but I don't see one for VZW. Can someone point me to the correct location to download SM-g973U and U1 firmware for VZW? Greatly appreciated and thanks for putting up with my lack of knowledge!
Edited: Found the files on sammobile. Will try the U1 (VZW) first. I'll keep my fingers crossed.

schwinn8 said:
I think the issue is that your phone is showing SPR/XAA/VZW. You say you're on a verizon MVNO (who, by the way?)... but your phone isn't seeing that. It's actually saying it's active for SPRint. The second one, XAA, means it's not able to detect the SIM type... and the third was that it was originally VZW, which you can't change and isn't really relevant. (That's just what the phone was "born" as).
Bottom line, your phone isn't seeing VZW or an MVNO as the active CSC nor the SIM card. In the past, the easy thing was to change the CSC to what you need, but I haven't found a way to do that actively. What's supposed to happen is that the CSC should update based on the SIM card and cell signal you're getting... but this doesn't always happen. I bought two phones - one switched with no issues, the other I could not get it to change no matter what I tried.
That said, the easiest thing is to clean flash the phone with ODIN to a VZW or your MVNO's ROM, so that (hopefully) the CSC updates automatically. You could also consider flashing a U1 (unlocked) ROM, as yours is not technically an unlocked ROM (U means it's a carrier ROM... which may be why it's not switching over?)
Again, I tried all of these on the second phone I bought, and nothing would switch it (my carrier is Total Wireless, which is a VZ MVNO, and actually shows up as Tracfone (TFN). I had to return that second phone and get another with TFN already activated, and that worked fine... so be sure you do this before you drop out of your return period.
Bottom line, you should be able to get this all working... my VOLTE/VOWIFI works fine... just a matter of getting you there.
Click to expand...
Click to collapse
Success! Was able to flash U1. VoLTE is now working. The CSC now shows TFN/TFN/VZW. Much appreciated!!!

Awesome, glad to hear that fixed it easily!
And TFN... I'm a fan there, too!

Hi! I'm having a similar issue with the same model and happy to see someone was able to enable VoLTE. However, most of what you said above is a foreign language to me. Would one of you be willing to give me a crash course in what you did?
Here's my specific situation. Last week (~1/4/23) Tracfone shutdown 3G. My Samsung Galaxy S10 (SM-G973U) says my network is set to LTE/3G/2G. I've read LTE is 4G, but still can't make or receive calls/texts, but data and 911 calls still work. Their tech support is no help.
From reading online it sounds like I may need VoLTE, not just LTE. Hence finding this thread. If one of you would be willing to spare some time to walk me through what you did I'd really appreciate it. In the mean time I'll try to figure out what "flashing" mean in a context that doesn't involve showing body parts
Thank you in advance!!

I'm on Tracfone (they were bought out by Verizon, BTW) - I was on Total Wireless before, which is now Total by Verizon. You might try contacting support again, as they are now VZ, and may have more help to offer.
My S10+ is running 975U1 now, and it works for VOLTE/VOWIFI properly. You may consider getting a U1 ROM installed, and maybe even the VZW (or TFN) version if available - that may get you working.
Did VOLTE ever work for you before on this or any other carrier? What is your CSC right now?

schwinn8 said:
I'm on Tracfone (they were bought out by Verizon, BTW) - I was on Total Wireless before, which is now Total by Verizon. You might try contacting support again, as they are now VZ, and may have more help to offer.
My S10+ is running 975U1 now, and it works for VOLTE/VOWIFI properly. You may consider getting a U1 ROM installed, and maybe even the VZW (or TFN) version if available - that may get you working.
Did VOLTE ever work for you before on this or any other carrier? What is your CSC right now?
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Click to collapse
Thanks for replying! I'm not entirely sure if VoLTE has worked previously. I bought this phone 6/2021 and have only haver had tracfone service for it. I did find in my setting that VoLTE calling is set to on so it seems like it should work. Of note, the 4Glte in my status bar has always been grayed out (I went back and looked at some old screenshots).
My current CSC is VZW/XAA/ATT.
I spoke with tracfone customer service yesterday and they had me reset my network setting and now I don't even have data and the 4Glte in my status bar that was previously gray has now completely disappeared.
Their customer service refuses to talk to me now (literally no one answers when it transfers to an agent) or they hang up on me, and no I haven't been rude, but I have told them I'm recording the call.
I bought a mint mobile package last night because I'm beyond frustrated with Tracfone. I'm worried I'll have the same problems with Mint. I'm not sure if my settings are screwed up or if it's just Tracfone. In any case things are worse now after talking to customer service yesterday.
I also notice there was no APN setting on my phone so I updated it today and restarted but no difference.
Thanks for any input!! Much appreciated. Sorry for the novel.

Ok, so based on your CSC, the phone is not seeing the SIM's carrier - it's showing XAA which means it's using the default settings, which is probably why your not getting VOLTE. The active CSC of "VZW" may be ok... depends on which carrier you're on with Tracfone. I think they're VZW only, but I'm not completely sure.
You may want to just get a new SIM card and get that activated. HOWEVER, the problem you'll likely face is that the phone was born ATT (last CSC). This means the IMEI won't match a "compatible" phone to Verizon, and they will flat out refuse to activate it (even though WE al know it will work fine). If you still want to do that, you will have to activate the new SIM on a VZ "compatible" phone, then you can swap it to the S10. Note that VZ complains about this when you talk to them... so don't tell them you're doing this... but I've done it many times and it works fine.
If your actual behind-the-scenes carrier is ATT, then you can do the activation with your phone without issue.
If none of this works for you, you can switch carriers to an ATT MVNO and you should be good to go.

schwinn8 said:
Ok, so based on your CSC, the phone is not seeing the SIM's carrier - it's showing XAA which means it's using the default settings, which is probably why your not getting VOLTE. The active CSC of "VZW" may be ok... depends on which carrier you're on with Tracfone. I think they're VZW only, but I'm not completely sure.
You may want to just get a new SIM card and get that activated. HOWEVER, the problem you'll likely face is that the phone was born ATT (last CSC). This means the IMEI won't match a "compatible" phone to Verizon, and they will flat out refuse to activate it (even though WE al know it will work fine). If you still want to do that, you will have to activate the new SIM on a VZ "compatible" phone, then you can swap it to the S10. Note that VZ complains about this when you talk to them... so don't tell them you're doing this... but I've done it many times and it works fine.
If your actual behind-the-scenes carrier is ATT, then you can do the activation with your phone without issue.
If none of this works for you, you can switch carriers to an ATT MVNO and you should be good to go.
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Click to collapse
OK some of that was still over my head. I'll see what happens with the Mint Sim... one f/u question now though. You said the ATT means my phone was "born" ATT. I bought my phone off backmarket and it was sold as "unlocked". Was that not true? How can I be sure in the future if I buy a used phone that's not from my carrier that it will actually be compatible?

Unlocked just means it's not locked to a carrier. That is true in your case, otherwise you wouldn't have been able to install ANY non-ATT SIM. So, you did the right thing to get an unlocked phone, and that is what you got.
The issue with compatibility is just the asshole carriers spreading lies. They do this to try to get people to buy THEIR phones, for no reason other than to make money and confuse consumers. The "born" CSC has no bearing on anything, really... neither does the carrier-specified IMEI. In your case, the XAA is good, which means it's a multi-carrier ROM, which works with all USA carriers.
Mint is a good idea - being an ATT carrier (IIRC), that should work and they should help you get it up and running even if they have to activate it. Good luck!

Awesome! Fingers crossed!! Thank you for your time and all the info❣
I'll try to remember to give an update in a few weeks for future readers

Goldie8709 said:
Awesome! Fingers crossed!! Thank you for your time and all the info❣
I'll try to remember to give an update in a few weeks for future readers
Click to expand...
Click to collapse
UPDATE: Switching to Mint worked like a charm! Once my number ported and I put the new SIM card in, service was instantaneous! I've had Mint for 3 weeks now and the service is so much better than with Tracfone! My calls go through nearly as soon as I hit call, the internet is faster.
I didn't need to do a thing either. No making APN settings, etc. I'm betting it has to do with what you said about my phone being born ATT. So funny because the software(?) is Verizon - shows the Verizon when I restart/power up. I still love my bastard phone
So thankful I didn't buy a different phone!!! Again thanks for all your help @schwinn8

Thanks for reporting back and letting us all know, and I'm glad it worked out well!
Yeah, the carriers pull this nonsense all the time... it's BS. The phones are all the same, only the ROM changes. If we can change ROMs (which we can) then there should be no reason to force users to specific IMEIs. But we know why they do this - follow the money. I encourage people to write to the FTC and FCC about this (I have).

SM-N910T on T-Mobile USA in 2023?

I am contemplating purchase of one of these phones, and tried entering some of their IMEI numbers in the imei checker at https://www.t-mobile.com/resources/bring-your-own-phone , and was shocked to find they are ALL described as "Incompatible".
This is a bit confusing after the articles saying the AT&T and Verizon versions would not work after Jan 2021 but that the T-Mobile version would continue working. I tried looking for a later article saying that support for the T-Mobile version this model was being cancelled but could not find any such announcement.
Is that IMEI checker correct? Or is it because the samples I checked may not have gotten the last modem update installed from T-Mobile?
Is anyone still using this phone (specifically the T variant) on T-Mobile in USA? I'm assuming that last update will be important, but does this still work once it is installed?
If yes to the above, do phone calls work as VoLTE, or is it doing the fallback to 2G?
I've also seen threads about enabling more LTE bands, has anyone done that on this phone? In particular is it possible to add support for B71 (600MHz), or is this radio hardware just too old to allow that?
Thanks much, I would really like to know whether I can use this phone or if I would need to find a different model.

https://swappa.com/blog/3g-network-shutdown/ Your phone is fine.

SM-N910T with 2ETI1 OTA modem update works fine. 4g/LTE Data, WiFi Calling works. Does not drop out of 4G/LTE for voice. SM-N910V w/ MODestROM v11 (6.01 TW-based N910VVRU2CQI2 ) w/ a vzw 2CTI baseband update, has working 4gLTE data, but no WiFi Calling, or VoLTE (falls back to 2g, but I still have 2g coverage here, so it's usable, if not optimum. Here's the thing: on the VZW phone, if I set the the salescode to TMB, suddenly VoLTE works, but the Setup pages/menus/statusbar are screwed up, so it's not really useable. Here's where it gets REAL interesteing. On a VZW phone w/ VZW 2CTI1 baseband, & VZW BL, flashed with a custom TMB ROM (trltetmo_N910TUVU2EQI2_Stock_Deodexed, debloated, but still TW), EVERYTHING works. But it's not stable, it periodically loses 4g/lte. What it tells me is that the VZW h/w is NOT THE PROBLEM. I've been at this all day, everyday since VZW turned off CDMA on 01/01/23 and killed my service here. Be warned: If you go down this path, you're gonna be mostly on your own. A LOT of dead links, 'retired' devs, etc. Everyone except you, me, and three other people here have long since moved on from this awesome phone. I'll help you if I can. I bought an SM-N910T , but the damn usb port is dead. Already changed the charging board, not the problem. It's the mobo. If I could identify the usb chip (if it's not the 805 itself, I'd change it. So I have a phone with no adb that I can't unlock/root. I'd much rather get my VZW phone fully working on TMB, since I'm heavily invested in the MODestROM. Haven't given up yet. But search my posts, you'll hear the deafening silence, lol.

Seeing this forum has so little activity, on 1/21 I ended up getting a used Moto E6 (XT-2005-3 is a tmobile aka carrier unlocked MetroPCS version). While overall this is not as nice a device and has fewer features than Note 4, it does cover what for me are the essentials - removable battery, SD card slot, support for 5.8GHz wifi. Best of all, it supports B71 which will be helpful for, well, making phone calls!
I still ponder someday getting one of these as a hobby device, but that would be second place to the E6 for use as a phone, and won't be for a couple more months yet (too many expensive household issues are taking their toll on my "toy" budget right now).
ForestCat said:
SM-N910T with 2ETI1 OTA modem update works fine. 4g/LTE Data, WiFi Calling works. Does not drop out of 4G/LTE for voice.
Click to expand...
Click to collapse
Thank you, this was the part I needed to find out. With that in place, the only thing missing would be the B71 coverage but the E6 is already in place for that.
Re your Verizon adventures, I have no experience with any of that. What I read about T-Mobile dropping support for the verizon version in the last network update is all I know, and I don't have the skills to dispute what they say there. The best I could do is offer some links to threads on this forum but on double checking them it seems you've already been there and got no answers.
The only thing I see that might help you with that is if you could update just the t-mobile modem without disturbing the verizon bootloader. I see you tried that but it didn't stick when using Odin. I don't know if it would be any different using SmartSwitch that seemed to work for MarineWonder as he posted at https://forum.xda-developers.com/t/...pgrade-on-jan-29th-2021.4224237/post-87464609 ?
Then again he may have been putting it on a t-mobile phone rather than mixing with the verizon bootloader so who knows?
My guess since it has been so problematic for you on the verizon phone is that you may need to only use a tmobile phone since that may be the only way to get the last t-mobile modem update. Bummer that the one you bought has a dead usb port. How are you charging it? Is there any chance you could return it to the seller since it came pre-broken? Then put the refund money toward another, hopefully working, tmobile phone? And would that MODestROM work on a non-verizon phone?
The only other thought I had is there are apps to connect to ADB over wifi. Sadly most of these need root. The ones that don't, seem to need at least once using a usb connection to do the "adb tcpip 5555" command to set it all up. . . . how annoying that it is all so circular!
There is also https://telnetd.en.aptoide.com/app?store_name=apps&app_id=59202144 , maybe a telnet connection could do the "adb tcpip 5555" command instead of using the USB connection? Sadly the documentation (at https://waxrain.com/docs/010.html ) appears to be written in Chinese, and I never had much luck with google translate.

The N910T still supports VoLte.. It is still compatible with cellular networks.