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.

N950N Olympics edition having trouble on TMobile

Hi all,
Received an Olympic edition note 8 (n950n) at the Olympics. We were supplied originally with a KT sim and even in the settings there's a "service provider" menu of KT related items. I have gotten back to North America and popped in my TMobile sim. It took resetting all network settings until I finally got LTE working on it.
However, volte doesn't seem to work at all. I even downloaded the shortcut master and went to ims settings to enable volte switch but still switches to 3g when I make a call. Similarly it can't even find hd calling. The option in shortcut master "hd voice" shortcut says "not found" when I try to launch it.
Ideally it seems as though I just need a different CSC but I don't want to void any warranty on this phone, especially given that I'm sure Samsung USA won't touch it since it's an international model.
Are the n950n's just lacking in many features?
Thanks!

I dont know how your carrier handles VOLTE, but my carrier requested me to go in person and there they activated the service

hgeek23 said:
Hi all,
Received an Olympic edition note 8 (n950n) at the Olympics. We were supplied originally with a KT sim and even in the settings there's a "service provider" menu of KT related items. I have gotten back to North America and popped in my TMobile sim. It took resetting all network settings until I finally got LTE working on it.
However, volte doesn't seem to work at all. I even downloaded the shortcut master and went to ims settings to enable volte switch but still switches to 3g when I make a call. Similarly it can't even find hd calling. The option in shortcut master "hd voice" shortcut says "not found" when I try to launch it.
Ideally it seems as though I just need a different CSC but I don't want to void any warranty on this phone, especially given that I'm sure Samsung USA won't touch it since it's an international model.
Are the n950n's just lacking in many features?
Thanks!
Click to expand...
Click to collapse
Hey There,
I'm glad to stumble upon an actual user of an Olympic edition.
Would you mind installing Samsung PhoneInfo app from playstore and sharing your current CSC Code, and your Device Model number - which I assume is N950N ?
I'm just looking for a way to obtain the bootanimation and the theme of it...

hgeek23 said:
Hi all,
Received an Olympic edition note 8 (n950n) at the Olympics. We were supplied originally with a KT sim and even in the settings there's a "service provider" menu of KT related items. I have gotten back to North America and popped in my TMobile sim. It took resetting all network settings until I finally got LTE working on it.
However, volte doesn't seem to work at all. I even downloaded the shortcut master and went to ims settings to enable volte switch but still switches to 3g when I make a call. Similarly it can't even find hd calling. The option in shortcut master "hd voice" shortcut says "not found" when I try to launch it.
Ideally it seems as though I just need a different CSC but I don't want to void any warranty on this phone, especially given that I'm sure Samsung USA won't touch it since it's an international model.
Are the n950n's just lacking in many features?
Thanks!
Click to expand...
Click to collapse
Short answer, sell it and get the USA version.
Sent from my SM-N950U using Tapatalk

Don't want to sell something that has such sentimental value to me

Product code SM-N950NZWZKTC
CSC code KTC

Additionally it doesn't seem to have the ability to have conference calls?

If you enabled all the switches through IMS setting & VoLTE still doesn't work, you'll need T-mobile CSC to get it working. Aside from the IMS settings, there are some VoLTE related settings in cscfeatures.xml. I have a N950F with modified T Mobile CSC, VoLTE, Wifi calling are working fine, I also have the VoLTE quick setting tile. But I'm rooted & is how I installed it
You'll need T Mobile CSC for wfi calling.
---------- Post added at 05:06 PM ---------- Previous post was at 04:56 PM ----------
Limeybastard said:
Short answer, sell it and get the USA version.
Sent from my SM-N950U using Tapatalk
Click to expand...
Click to collapse
Heck no, I say root it, I'd never trade it for a US Snapdragon but that's just me. Can easily get VoLTE working along with many more features.

shouren04 said:
If you enabled all the switches through IMS setting & VoLTE still doesn't work, you'll need T-mobile CSC to get it working. Aside from the IMS settings, there are some VoLTE related settings in cscfeatures.xml. I have a N950F with modified T Mobile CSC, VoLTE, Wifi calling are working fine, I also have the VoLTE quick setting tile. But I'm rooted & is how I installed it
You'll need T Mobile CSC for wfi calling.
Click to expand...
Click to collapse
Will the Tmobile CSC work on this particular device? Tmobile csc i thought would not work on the 950n's as its not the same hardware?
where can i get the csc?

hgeek23 said:
Will the Tmobile CSC work on this particular device? Tmobile csc i thought would not work on the 950n's as its not the same hardware?
where can i get the csc?
Click to expand...
Click to collapse
That I have no idea, I have no idea if flashing just the CSC file works between different model/chipset phones. I assume not. I rooted my phone in 2 days so I have no experience flashing official CSC files.
I'm using a modified version of TEKHD's S8 T-Mobile transformation pack. It's an early version of the following mod that I further modified for myself.
[MOD] Exynos T-Mobile CSC Wifi Calling, VoLTE etc for N950N / N950F
The person who made it has a N & specifically made it to get VoLTE & WIFI calling to work on N models. I'm using an earlier version cause it works fine on F models but still had issues on N models. To summarize that thread, he finally got it working fine for N models with nothing additional needed. But you need TWRP & root to install it.

Limeybastard said:
Short answer, sell it and get the USA version.
Sent from my SM-N950U using Tapatalk
Click to expand...
Click to collapse
shouren04 said:
That I have no idea, I have no idea if flashing just the CSC file works between different model/chipset phones. I assume not. I rooted my phone in 2 days so I have no experience flashing official CSC files.
I'm using a modified version of TEKHD's S8 T-Mobile transformation pack. It's an early version of the following mod that I further modified for myself.
[MOD] Exynos T-Mobile CSC Wifi Calling, VoLTE etc for N950N / N950F
The person who made it has a N & specifically made it to get VoLTE & WIFI calling to work on N models. I'm using an earlier version cause it works fine on F models but still had issues on N models. To summarize that thread, he finally got it working fine for N models with nothing additional needed. But you need TWRP & root to install it.
Click to expand...
Click to collapse
I need to flash a new kernel? Firmware? Will this replace the Olympics bootscreen?

@hgeek23 Did you see my PM ? Thanks

hgeek23 said:
I need to flash a new kernel? Firmware? Will this replace the Olympics bootscreen?
Click to expand...
Click to collapse
It won't replace the Olympics boot screen but it will trip Knox & may void warranty (not sure what warranty laws are from the original COO, some countries don't void warranty for tripping Knox). But if you are in the US, you can't claim warranty on the phone in the US anyway.
You'd have to install TWRP & root your phone to install the mod I linked. But being how rare that phone is, I wouldn't do it unless you find a copy of the stock Olympics FW for that phone in case anything happens. Seems like others have been looking for it but can't find it yet. Other say it's just a theme that can be installed but if it has a different boot screen then I doubt it's just a theme for the theme store.

hgeek23 said:
Hi all,
Received an Olympic edition note 8 (n950n) at the Olympics. We were supplied originally with a KT sim and even in the settings there's a "service provider" menu of KT related items. I have gotten back to North America and popped in my TMobile sim. It took resetting all network settings until I finally got LTE working on it.
However, volte doesn't seem to work at all. I even downloaded the shortcut master and went to ims settings to enable volte switch but still switches to 3g when I make a call. Similarly it can't even find hd calling. The option in shortcut master "hd voice" shortcut says "not found" when I try to launch it.
Ideally it seems as though I just need a different CSC but I don't want to void any warranty on this phone, especially given that I'm sure Samsung USA won't touch it since it's an international model.
Are the n950n's just lacking in many features?
Thanks!
Click to expand...
Click to collapse
Maybe you've got the rare paralympic edition of Note8 which isn't capable of it? (I know, tastefully offensive. I'll be going to hell for that joke)
On a serious note, since it's the N950N which is similar to the N950F afaik, you're better off asking TMobile directly about any connectivity issues.
Usually like others have previously mentioned, should be CSC related but f.e. (if I'm not mistaken) due to the OMC folder/ structure, nearly all country CSC are included. Just the CSC features aren't accessible unless you replace the specific CSC with a modified one from S8/S8+.
If TMobile can't fix it or help you out, you're choice would be to root, double check with a N950F/N950N user if they have volte or (someone has to jump in here to verify) try flashing -if available- factory binaries for specifically USA.

I doubt T-Mobile will help or can even do anything being an international phone. My F on T-Mobile USA worked perfectly fine. You don't need IMEI provisioning with T-Mobile USA like you do with some carriers like AT&T. My speeds were great out the box, better than my T-Mobile Note 5, just didn't have VoLTE & Wifi calling until I enabled them w/ root. We now have 2 more Note 8s in the household, U T-Mobile variants. Speeds are pretty much exactly the same as my F.

shouren04 said:
That I have no idea, I have no idea if flashing just the CSC file works between different model/chipset phones. I assume not. I rooted my phone in 2 days so I have no experience flashing official CSC files.
I'm using a modified version of TEKHD's S8 T-Mobile transformation pack. It's an early version of the following mod that I further modified for myself.
[MOD] Exynos T-Mobile CSC Wifi Calling, VoLTE etc for N950N / N950F
The person who made it has a N & specifically made it to get VoLTE & WIFI calling to work on N models. I'm using an earlier version cause it works fine on F models but still had issues on N models. To summarize that thread, he finally got it working fine for N models with nothing additional needed. But you need TWRP & root to install it.
Click to expand...
Click to collapse
Hey there, I thought I recognized the name. Remember me? One of the first to test and rip open the F model to try and figure out the LTE issue / carrier aggregation issue.
I've read through some pages over on the OEM Lock thread ... so to conclude, they figured out the issue with the OEM lock disappearing, but did they ever figure out the carrier aggregation for using F/N model 100% on T-Mobile??
I know people with the F and N models that are still suffering from carrier aggregation and like this Olympic Edition model, which is just a N model with a cool back white Olympic cover. Those who plan to use this on T-Mobile may face the LTE connectivity (carrier aggregation) issue..
For those in really good reception areas may not seem like they have an issue, but that is because they are connected to a really strong (single) signal/frequency, which makes it seem like everything is fine...
Would you be able to provide links to any progress regarding this issue? Has it been solved? If so, it's likely buried in the pages somewhere in the other threads....:highfive:

iunlock said:
Hey there, I thought I recognized the name. Remember me? One of the first to test and rip open the F model to try and figure out the LTE issue / carrier aggregation issue.
I've read through some pages over on the OEM Lock thread ... so to conclude, they figured out the issue with the OEM lock disappearing, but did they ever figure out the carrier aggregation for using F/N model 100% on T-Mobile??
I know people with the F and N models that are still suffering from carrier aggregation and like this Olympic Edition model, which is just a N model with a cool back white Olympic cover. Those who plan to use this on T-Mobile may face the LTE connectivity (carrier aggregation) issue..
For those in really good reception areas may not seem like they have an issue, but that is because they are connected to a really strong (single) signal/frequency, which makes it seem like everything is fine...
Would you be able to provide links to any progress regarding this issue? Has it been solved? If so, it's likely buried in the pages somewhere in the other threads....:highfive:
Click to expand...
Click to collapse
Yes I remember you. I may not be the best guy to answer your questions but I'll share what I remember.
If you remember, I was just about the only guy in those threads that didn't experience any of the issues you guys did. I'm still using an early version of KT's TMO zip which was basically a slightly modified version of tekhd's S8 zip. The versions to follow is when they started changing more & had issues as it was later found out that the TMB_keystrings.dat from N950U was the cause. Once they replaced that file the issues were reported to have been resolved. I think the current version is like 9m or something I like, I'm using 3a & always have been, never tried any later versions & is probably why I never experienced those issues.
At home my reception is not very good nor are speeds, I get 20-40mbps depending on the time of day. This was the same before I used the zip. My CA combos were different than what the zip gave me but I still had the combos that get's used the most in my area. Around town in good areas I can get 80-135mbps. I stopped checking as I put the subject to rest a while ago.
A few months ago my parents both got Tmobile N950Us. I compared my F with the TMO zip & speeds are pretty much the same, sometimes my F is slightly faster, sometimes the U, but not a big difference so I consider that other factors & call them the same. I've even tried a speed test at a local T-mobile store & the speed was like 6mbps (that area I know doesn't have good coverage) on a U where mine was getting just under 20. Still I'm not saying my F is any better but since I was able to test actual T-Mobile U variants, I don't believe my phone to have any issues with speeds & CA in my area.

Yes the Olympics edition is simply an N with a theme applied and physical cover with the logo on it. the bootscreen is an olympics logo etc.
Merging calls doesnt seem possible, i dont know why. LTE frequently drops on Tmobile now and just goes to 3g or no service at all.
Volte not working either.

I had a similar situation. I bought my phone (N950F) from abroad. Although the phone was in the compatible devices list of my carrier company, they told me that VoLTE could not be used on phones taken from abroad (silly reason). VoLTE enable is carried out by sending a request SMS to the carrier. I put my SIM card into a friend's phone, and sent the request through it. My carrier enabled my SIM card. I put it back to my phone and voila! I have been using VoLTE since then without any problem.

Just wanted to post a final kind of update and that is that the above referenced CSC for Tmobile worked well.

Question Samsung Galaxy s21 ultra Snapdragon RF test

Friends I have a s21 ultra Snapdragon SM g9989 hong kong. To be able to use 4G+ I used the google phone with code *#*#27663367382#*#* and I could activate the bands I need. But when you updated android 12, the code no longer works and I can't activate the bands

Upgraded to 12, first mistake.
You'll need the new access code... good luck with Samsung tech support, you'll need it.
Maybe roll it back if possible...12 is known to be a wittle b****.

A local phone shop may be kind enough to share the new code with you or give a work around.
Samsung tech support is notoriously unhelpful.

blackhawk said:
Upgraded to 12, first mistake.
You'll need the new access code... good luck with Samsung tech support, you'll need it.
Maybe roll it back if possible...12 is known to be a wittle b****.
Click to expand...
Click to collapse
blackhawk said:
Upgraded to 12, first mistake.
You'll need the new access code... good luck with Samsung tech support, you'll need it.
Maybe roll it back if possible...12 is known to be a wittle b****.
Click to expand...
Click to collapse
Ok so download a short cut manager app. And the option is under phone settings network

johnb4200 said:
Ok so download a short cut manager app. And the option is under phone settings network
Click to expand...
Click to collapse
So you're good to go?

blackhawk said:
So you're good to go?
Click to expand...
Click to collapse
just follow those steps in shortcut maker

Sylarx7 said:
Friends I have a s21 ultra Snapdragon SM g9989 hong kong. To be able to use 4G+ I used the google phone with code *#*#27663367382#*#* and I could activate the bands I need. But when you updated android 12, the code no longer works and I can't activate the bands
Click to expand...
Click to collapse
I posted instructions for you to be able to unlock any band you want

johnb4200 said:
View attachment 5529473View attachment 5529475View attachment 5529477View attachment 5529473View attachment 5529475View attachment 5529477just follow those steps in shortcut maker
Click to expand...
Click to collapse
Be careful with that app. There are somethings you don't want to trigger to run. Use only specifically what you need. I wouldn't go nuts exploring with that.
Took me a couple days to find and repair a system app setting that was altered. It wasn't easy, and the only other way to repair it be a factory reset.
Do Not open Android system apks with it

I just use Samsung band selection on google play

The functionality as shown can only be used to force select specific bands to be used - while preventing others to be used - all within the current possibilities of the phone. It will however not unlock/activate any bands on your phone nor add any new.
Also, when bands in your selection are not supported by your network or by your provider of by your phone, they will not be employed and are in fact being ingnored.
It can still be useful to make band selections though.
My main use case for band selection app/hidden settings (both do the same!) ‐ in combination with cell mast info from Cellmapper App ‐ is to prevent unnecessary and undesired network/cell mast switching at my holiday house, which is situated in a remote rural location with poor reception. By selecting the right set of bands (and thus switching off others), I can force my phone to remain connected to one particular cell mast. That way the phone battery is not being depleted by constant scanning and reconnecting to different masts. As a result the standby time is increased (in my situation) by more than 15 hours.
Other use case for me is at my home location, to force selection to a particular mast, not the nearest with strongest signal, to enfore use of higher frequency bands and CA, to get greater data speeds - thereby increasing speed from 10 Mbps to 50 Mbps in comparison with automatic network selection.
By the way, there is no harm or danger to use these band selections apps or settings. Settings made wrt the network mode in regular (unhidden) network mode settings, will override/switch off and reset the band selections you have made. (E.g. set network mode to automatic)

mpore14 said:
I just use Samsung band selection on google play
Click to expand...
Click to collapse
Good suggestion. That is much easier and it invokes exactly the same settings.

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!
Click to expand...
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.
Click to expand...
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-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.
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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.