Database Develop

Custom Excel program for WM6.0

Can anyone recommend a person who could write an excel based program that could be copied to a WM devise? I am new to this forum and do not have the knowledge or the time to develop the program, but i am willing to pay for it.
Thanks

notthatcreative said:
Can anyone recommend a person who could write an excel based program that could be copied to a WM devise? I am new to this forum and do not have the knowledge or the time to develop the program, but i am willing to pay for it.
Thanks
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Why not install office on your mobile. http://forum.xda-developers.com/showthread.php?t=310832
Or flash a ROM with office installed, most do
Ta
Dave

I agree, both are a great solution, but this project is not for myself. This project is more for job. This board has given me an idea for my customers, which do not own a Tilt. If this excel file was turned into a .cab file, my customers could add it to their PDA devise.
I'm not that familiar with program creation within a WM devise, but after lurking around this board for the past 6-9 months, I thought someone would know!

This is not a tilt specific CAB. It's a Window Mobile 6 version it cab go on WM6 any device.
Ta
Dave

I believe what you are saying is that a .cab can be installed on any WM devise. I agree. What i need to do is create the .cab file.

Yes you are correct. CAB files can go on any device.
I'm still unsure on what your requirements are. Do you want a copy of Excel to install on WM6 devices, then that's what I posted first time round? Nearly all standard WM and PDA's have a version of office installed, anyway.
Or, are you wanting a program like Excel Mobile but with "extra" features.
I think you need explain what your requirements are (without giving too much away, if you don't want to), so we can build a better picture of what you want.
Dave

You raise excellent questions as i'm not sure what is available. Unfortunatly, i cannot speak the language of this forum very well and am unsure of options available.
Currently, i have an excel spreadsheet with the calculations complete, but was unsure of how to create an "engine" to drive the program if the end user did not have excel available. This excel file i've created uses basic calculations which produce a number generated by data entered by end user. I am assuming an engine, or what i call a "cab" file is required!?!
Also, I'm not married to the idea of using excel and am open to using other programs if nessesary.
Am i making things a little clearer?
Thanks

like daveshaw said, most wm devices already come with excel in it. and if your customer does not have excel on their devices, then they can install it using the cab files

It sounds to me like you want to take a specific spreadsheet that was created using Excel, and somehow compile it as a program that doesn't need Excel to run. I don't think this is possible. You can't drive a car without its engine.
If you really wanted to pursue that route, I think what you'd need is someone who can dissect and analyze your spreadsheet, and rewrite it in another language (like C++ ), which can be compiled into a self-contained, executable file. Wish I could help you there.
I think your only realistic option is to install Excel on all the WM devices.

sensei909 said:
It sounds to me like you want to take a specific spreadsheet that was created using Excel, and somehow compile it as a program that doesn't need Excel to run. I don't think this is possible. You can't drive a car without its engine.
If you really wanted to pursue that route, I think what you'd need is someone who can dissect and analyze your spreadsheet, and rewrite it in another language (like C++ ), which can be compiled into a self-contained, executable file. Wish I could help you there.
I think your only realistic option is to install Excel on all the WM devices.
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Everyone, thanks for you help. Sensei909 has figured me out. It sounds like i need someone to who can rewrite this in another language. Can anyone point me in that direction....Website, company, friend???

Re:
Hello, few questions:
1) What devices will your customers use?
2) If they are Windows Mobile-based, what versions are here?
3) Do you have Excel Mobile on your Tilt?
4) Did you try to open your spreadsheet using your Excel Mobile?
5) If your spreadsheet is created using Excel 2007 on desktop, did you install Office Mobile 6.1 from Microsoft site?

Build a java midlet? Almost all phones have java. I can see it doing basic calculations very easily.

Windows Mobile App Repository

There is currently one app repository on XDA the thread is as follows.
http://forum.xda-developers.com/showthread.php?t=471576
However, I am trying to develop similar software which allows users to register with the website and create different profiles, create packages, revise packages, and search by device, WM version, package name and other traits.
For example, on my Kaiser I like to have the total commander, Skype, pocket rar, Google maps, and other software. I would like to be able to select the necessary programs either via PPC software or the website and automatically download and install the software on my devices. (a lot like tierautoinstaller) in addition when new versions come out I would like to have to option of automatically installing the updated version.
The package system would work much like Apt-get from the debian Linux distribution http://en.wikipedia.org/wiki/Apt_get. Each package would have an owner and contributors. The owner is the person who created it and can delete it. Contributors will have assignable powers to modify package information and release new versions of the program.
Each user will be able to select his/her packages and they will be saved in the database. The cabs will can to be retrieved from either the software on the device (still needs to be made) or the website (work in progress).
Currently I have a mySQL database as my backend and have created the basic dynamic webpages in perl which can browse, search, create and modify packages. Each package will have an external url and an internal cached copy for fault tolerances. More details will be disclosed as my development contuines.
If this sounds like something you will use or have any suggestions please let me know. Work has been kicking my butt lately but as soon as I finish the user registration part of the website I will put it up for a few test trials.
Pizzaroll
Mods: Since I currently own a Kaiser and only have software for a Kaiser I would like to keep this thread here until the initial testing phase is complete and I am ready to expand to other devices.

I don't get why there are 3-4 (likely 6-12) app stores out there, all incomplete, all with few apps listed. Rather than build another one, how about working with one which fits your ideas and contributing.
http://forum.xda-developers.com/showthread.php?t=480476
http://forum.xda-developers.com/showthread.php?t=436127
And even one to browse Freeware PocketPC:
http://forum.xda-developers.com/showthread.php?p=3268926

Windows Phone 8 Root/other Certificates Maybe?

Hey Guys,
Below is a list of the things that my HTC 8x does when it checks for Windows Updates. I am waiting for Microsoft's server to decide to give me a new firmware, so I decided to sniff out the TCP stream. Of note, I found the following:
1. Phone contacts http://fe1.update.microsoft.com/WP8/MicrosoftUpdate/Selfupdate/5_UssDetection.dll
The Phone goes out and fetches this dll onto the system. It references the following certificates (which you can download):
root cert http://www.microsoft.com/pki/certs/MicRooCerAut_2010-06-23.crt
production cert http://www.microsoft.com/pkiops/certs/Microsoft Windows Phone Production PCA 2012.crt
time stamp PCA? http://www.microsoft.com/pki/certs/MicTimStaPCA_2010-07-01.crt
2. After that, it goes and fetches the following cab file: http://sds.download.windowsupdate.com/wp8/MicrosoftUpdate/Redir/duredir.cab. This cab file contains a single xml file called wuredir.xml. It has two values: the clientServerURL and the ReportingServer URL.
3. After this, some https traffic occurs to the clientserver URL. I am guessing this is it checking for updates.
4. Then it posts to http://statsfe1.update.microsoft.com/ReportingWebService/ReportingWebService.asmx with a SOAP action of http://www.microsoft.com/SoftwareDistribution/ReportEventBatch with a whole bunch of info on the phone.
The User Agent being used for all of these communications is as follows: Windows-Mobile-Device-Update-Agent
If this dll it is fetching is unsigned, I wonder if we could have some fun....I am also wondering what happens if we develop and sign an xap with Microsoft's certificate if it will allow us to do more things within the OS.

Sign with Microsoft's private key? If you have access this then your about to become very popular
Sent from my Arc using xda app-developers app

Hmm, the 5_UssDetection seems to be a normal PE32 .dll. Not .NET compiled. I don't see any COM Imports/Exports for it so finding this out may be a little difficult. I haven't used any tools like IDA though, just a normal PE explorer program.
This is good information though. I wonder if GoodDayToDie may have some further input?

Nice find. I've been monitoring phone traffic myself but hadn't caught this exchange yet.
The fact that it checks external cert files is very interesting. Typically, I would expect this to be using "certificate pinning" where the public key of the signing cert is stored internally in the software, and no other signature is trusted (even if it chains to a CA that is installed on the phone and would normally be trusted). MS does use pinning in a number of places; for example, this is how the original ChevronWP7 Unlocker was broken, and is used when adding a Microsoft account to the phone or when that account is updating. However, I figure there's an excellent chance that pinning is *not* being used in at least one place where it really should be (this can be tested using tools like Fiddler or Burp, which have the ability to intercept SSL traffic using a cert that chains to a cert installed in the phone's trusted authorities store).
If pinning isn't being used, it may be possible to modify/create our own detection DLL, then create our own CA cert, install the public key on the phone, use the private key to sign an intermediate cert (that we also create, and have the private key for), and use the intermediate cert to sign our customized DLL. If necessary, we could even intercept the lookups that the phone performs and control what is returned (assuming the lookups are actually over HTTP, or at least unpinned HTTPS).
The probability that the file is unsigned isn't even worth considering; it's quite likely that Microsoft is using a mandatory signing level on WP8 for all executable code. Unfortunately, if they are doing that, it's also likely that it's set to require a cert which chains to the MS root cert (this is how Windows RT is by default), which is effectively a form of system-wide cert pinning. However, if you want to check, signtool in the Visual Studio Command Prompt can dump authenticode certs on a file.
Reverse engineering the detection DLL is quite possibly worthwhile even if we can't modify it, too; it'll provide insight into the update process, which is one of the best places to mess with a system. It runs with high privileges and explicitly is capable of modifying system code.

That sounds quite enticing! I wish I knew x86/ARM assembly :/. I'll see what the sign tool outputs in VS

It feels great to see that you're here GoodDayToDie You helped out a lot on WinPho 7 for HD2 (a device I'll soon repurchase).
Hopefully there'll be some advancements on the "jailbreaking" of Windows Phone 8

I would be surprised if WP8 wasn't using the same code signing requirements as Windows RT.
As far as hijacking that dll goes, unless we can find an immediate privileged code execution exploit in it all it's most likely to do would be to give us write abilities to the FS, and there's a huge 'if' attached to that. That would be a big step if possible, though.
Something that would be interesting to check is if an EXE compiled for Windows RT (cdb, for example) would be capable of running on WP8. If MS used the same signing certificates it may be possible to put enough of Windows RT's dependencies on WP8 to allow it to run a simple console application. Obviously we wouldn't have any console windows or the sort, but it should be possible to capture output if it worked.
We have a decrypted OS dump around somewhere, right? It should be simple to check if they use the same signatures.

Good call on checking the signatures. I'd also like to take a look at reverse engineering the OEM apps again; even if they don't give us a device-agnostic hack directly, they may reveal interesting things about the WP8 app model internals and also may give device-specific breaks which can be used to gain the knowledge we need for crafting device-agnostic ones.
Slightly off-topic:
The zipview exploit still (sort of) works. Hard to believe, but I bet MS just recompiled the program for NT's Win32 and didn't bother with it beyond that. Decent chance that the same holds for the XAP installer, though I haven't tried yet. However, A) the filesystem layout has changed, so write-only access is even more poking blind than it used to be, and B) zipview may be running with lower privileges than it used to. On a simple test ZIP (attached for your testing pleasure), I can open files and create directories up to three levels above the zip root, but no further. Trying to open a file in a folder directly higher than that gives a "cannot extract to a read-only location" error, and trying to open a file inside a subfolder above the third level up gives a generic error message (probably due to failing to create the folder).
Also, I got wired tethering working on my Ativ S today. I'll create a post about doing that if nobody else has done so yet (it was almost identical to the WP7 Samsung devices, the only hard part being finding the right 64-bit drivers). WindowBreak didn't work, though (the folder that it extracts at is above the permissions cutoff, which makes me suspect zipview can't write to the drive root) and I don't think the subcomponent of the Diagnostics app works the same, either (a lot of the diagnostics codes have changed; we should learn the new ones).I don't even know if WP8 understands provxml (it's historically a CE feature, not an NT one), although I found references in the Diag app to provxml being "ready".

Here's what I came up with for a file list from some rudimentary (and possibly inaccurate) parsing of a .ffu: http://pastebin.com/hX6qJQeA
Got that from RM820_1232.2109.1242.1001_RETAIL_nam_usa_100_01_95122.ffu.

Great, thanks for that! Looks like provxml is definitely still here, and that's probably good. I'll bet they changed some things though, to make it more NT-ish (support for proper ACLs, for example). I should review those included provxml files for a look at how the phone is currently configured. Lots of potentially interesting .REG files too. I'll have to try some more things here!

No problem. All I did was pull out all text inside '<DevicePath>' tags inside one of the FFUs for the AT&T Lumia 920.
From looking at the FFU it appears to be a collection of CAB archives (or packages) encapsulated in some proprietary format. WP7.x tools don't work on them, sadly.
Edit: I'm blind sometimes, there is a tool to mount them and it does work.
More edit: Different signatures.
More more edit: Windows RT refuses to run the WP8 binaries without a jailbreak.

Hmm... but with jailbreak, do the binaries run? I mean, they're NT Win32-based PE binaries compiled for THUMB2 architecture, so I'm sure they can at least be executed, but do they actually run or do this simply error out or crash immediately?
It would be interesting to compare the certificate chains of RT and WP8 binaries. As far as I know, the default restriction level on RT should allow anything that chains to the Microsoft root Authenticode cert to run, which means either that we misunderstand that restriction or that the WP8 signatures chain to a completely different cert. I'm guessing it's the latter, but that does surprise me. I could understand if RT used the "Windows" signing level and WP8 binaries wouldn't work; despite having Windows in the name, using the Win32 API, and running on the NT kernel, the Windows Phone team is separate from the Windows team and quite likely has its own signing keys. I would think that an OS which accepts Office and DevDiv/Tools signatures (unless Office and the debuggers were re-signed by the Windows team? I haven't checked) would accept Windows Phone signatures too.

GoodDayToDie said:
Hmm... but with jailbreak, do the binaries run? I mean, they're NT Win32-based PE binaries compiled for THUMB2 architecture, so I'm sure they can at least be executed, but do they actually run or do this simply error out or crash immediately?
It would be interesting to compare the certificate chains of RT and WP8 binaries. As far as I know, the default restriction level on RT should allow anything that chains to the Microsoft root Authenticode cert to run, which means either that we misunderstand that restriction or that the WP8 signatures chain to a completely different cert. I'm guessing it's the latter, but that does surprise me. I could understand if RT used the "Windows" signing level and WP8 binaries wouldn't work; despite having Windows in the name, using the Win32 API, and running on the NT kernel, the Windows Phone team is separate from the Windows team and quite likely has its own signing keys. I would think that an OS which accepts Office and DevDiv/Tools signatures (unless Office and the debuggers were re-signed by the Windows team? I haven't checked) would accept Windows Phone signatures too.
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As far as running, some have given me console output, but I haven't gotten a single GUI one to start. I've been considering on looking to see how complex the UI is to see if I can write some sort of WP8->Win32 translation layer. There are just so few WP8 xaps floating around that it's not really worth looking into, though.

I don't expect the GUI to work; the whole model (with the Back history and all that) is going to rely on stuff not found on Windows Client. Cool that you're able to get some CLI apps to work (which is funny in and of itself; WP8 doesn't support a terminal interface). This is only post-jailbreak though? That still seems weird, since the signatures chain to the MS root CA. Very weird. I'll poke around myself once I download a ROM to explore (busy with work at present).

I haven't really found any to work, per se, I've just gotten console output, generally in the form of an error message or a help prompt. I can't recall which files exactly I had tried with, though. I mostly just poked through system32.

GoodDayToDie said:
I don't expect the GUI to work; the whole model (with the Back history and all that) is going to rely on stuff not found on Windows Client. Cool that you're able to get some CLI apps to work (which is funny in and of itself; WP8 doesn't support a terminal interface). This is only post-jailbreak though? That still seems weird, since the signatures chain to the MS root CA. Very weird. I'll poke around myself once I download a ROM to explore (busy with work at present).
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the GUI classes of windows phone are not compatible with the standard .Net library or windows RT. The only way to get them running is through some sort of virtual machine. Some MSFT guys confirmed this a few months back at a training course about W8 RT.
Basically, it is kinda difficult to have WP8 apps show any GUI at all outside of their WP8 runtime.

netham45 said:
Here's what I came up with for a file list from some rudimentary (and possibly inaccurate) parsing of a .ffu: http://pastebin.com/hX6qJQeA
Got that from RM820_1232.2109.1242.1001_RETAIL_nam_usa_100_01_95122.ffu.
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In regards to the file "MMOS.wim", has anyone managed to extract it/analyze it?
I couldn't find anything about it online. I am able to mount the file to a virtual disk and view its contents, but I am not able to view/read/extract any of these files from the drive. Trying to copy any file from the drive gives a system error/exception message that I have never seen before.
Are the files inside of "MMOS.wim" even useful?
---------- Post added at 12:13 PM ---------- Previous post was at 11:22 AM ----------
mcosmin222 said:
the GUI classes of windows phone are not compatible with the standard .Net library or windows RT. The only way to get them running is through some sort of virtual machine. Some MSFT guys confirmed this a few months back at a training course about W8 RT.
Basically, it is kinda difficult to have WP8 apps show any GUI at all outside of their WP8 runtime.
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Not difficult, more like impossible lol.
The entire native UI is very independent. It is best described as one single app that has multiple pages. The start menu is a page, settings app is a page, office 365 is a page, etc.
These different pages all cross-reference resources from each other and can modify each other. However, they are all compiled separately. Each "page" contains it's own resources and GUI markup in a dll, along with native code to interact with the markup. This native code can also call functions and access resources from other "page" dll's. There are no compiler dependencies between the "pages" when being created, only during actual runtime.
Things are very "coupled" by this model on purpose. Changing code/functionality in the startmenu.dll could potentially break everything. It is designed so that you cannot target and modify a specific element or feature without updating code in other areas of the system.
Basically, you need full access and understanding of the gui layouts/code to modify it.
The only reasonable possibility is the ability to modify the markup code (think XAML) to change layouts and visuals. But even that possibility is made difficult since the markup is compiled. However, no information is lost during the compilation, meaning that the markup can be decompiled back to its original form.
Windows 8/RT uses DUI (DirectUI), a similar framework, for all of it's native GUI elements.
Windows Phone 7/8 uses UIX/Splash.
Asking a former Microsoft employee about UIX/Splash is like asking a former U.S. government agent about Area 51. They seriously fear for their lives.

I would avoid using the word impossible as of yet. With a layer of emulation above RT the thing should "run".
It might be possible to have an app compliant with the app store requirements (as in not require jailbreak) on RT to emulate the WP8 GUI model, but that would imply interpreting the XAML code and emulate it JVM style, but it would be a lot of work.
I wonder if the WP8 emulators would prove to be of any use...

mcosmin222 said:
I would avoid using the word impossible as of yet. With a layer of emulation above RT the thing should "run".
It might be possible to have an app compliant with the app store requirements (as in not require jailbreak) on RT to emulate the WP8 GUI model, but that would imply interpreting the XAML code and emulate it JVM style, but it would be a lot of work.
I wonder if the WP8 emulators would prove to be of any use...
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My GUI post was in regards to the native GUI. I didn't realize that you were talking about WP8 apps running on Windows RT. I thought you meant the other way around lol.
Couldn't this potentially be pointless? Microsoft Job posting was looking for developers interested on deploying .appx on Windows Phone I believe. So that means they are going to make .appx the universal model for all platforms and not .xap in the future. With that said, they might be stopping .xap development completely in the future.
Who would develop an .xap for Windows Phone when you can develop .appx and have it work on Windows Phone + Windows RT + Windows 8 + Xbox?
Just some thoughts. I think trying to get .XAP running on Windows RT is pointless to pursue right now, since the time researching would be better spent in other areas of development.

Im not sure how they are going to make appx run on WP8. The WinRT model is obviously tuned towards bigger screens. How would you use a charms bar on WP8? In fact, how would you use any of the W8 stuff on WP8?
I think a lot of people would like to run emulated WP8 apps on their tablets, since some apps have not been ported yet.
While I do agree this is kinda pointless, it's a nice way of learning new stuff.

[Q] WP8, Phone>Documents & Text files

Hi all, just a quick question regarding the functionality of Wp8 that I am fighting with, that I need to resolve or another WP phone is going back to the supplier [I did the same with WP7].
First off, apologies if there's an answer that I haven't managed to find.
I currently have an HTC HD2 running very nicely on WM6.5, however, it's been creaking a bit recently & I'd decided with a favourable review of WP8 that I read the other day suggesting that finally the device can be plugged into a PC & seen as a USB drive, that the time was right to move forwards.
Now that I have the Nokia Lumia 820 & WP8 however, I still don't think I can get it to do what I need it to do.
ALL I would like to do, is be able to copy text files from PC to WP8, & then display them on the phone with text wrap switched off.
Easy hey? Well if so, I haven't worked out how to do it yet!
I plug the phone into my PC, & an Explorer window fires up on the PC [XP] showing 'SD card' & 'Phone'. Drilling down one level on the latter gives Documents, Music, Pictures, Videos etc.
The only way I can get to see the Documents folder on my Phone appears to be via Office Mobile, under 'places' > phone. It appears to be very fussy about what it allows to be displayed there - I can see .PDF, .DOC, .XLS & .TXT files [but not .LOG. .ONE, .ZIP etc (which remain 'hidden')].
When I tap a .TXT file, I have no choice of how to open it, Office Mobile pounces & that's that. Having got this far, all I would now like to do is switch off text wrap [so that it'll view in a usable manner] because there doesn't appear to be such an option.
I have scoured the Store, & the best I've found is 'Text Reader', though this requires that I load it via email [upload a file to Hotmail or wherever with a .LOG (or similar) suffix & away you go, which it then downloads & stores in its own sandbox]. Ok, but faffy.
I believe that other progs might enable transfer via the cloud [Skydrive or whatever], but because of the nature of the data [& the fact that I don't want my data in anyone else's hands], this is out too.
I've spotted a couple of other quirks.
Office Mobile also does not allow you to display the folder hierarchy that may exist in Phone>Documents, just giving a flat filesystem, which makes finding a file in thousands, say, horrible. All I'd like to do is exactly duplicate the hierarchy that exists on the PC [& then I am always looking for things in the same place on either device].
I have also noticed that Office Mobile Word sometime hangs part way through a file. e.g. on loading a 1mb file, & searching for a text sequence I know to be on the last line, it hangs on a line part way through the file [say a 1/3 of the way in]. Not great, & I have the odd file that's c.10mb so I dread to think with that.
Words fail me, & once again I am hugely disappointed with MS. Please, please get the odd decision right & maybe WP will be at the top of the pile again as it was with [the sometimes awful, but very functional] WM.
I am hoping that someone will explain an easy way to do this, & that I can finally move forwards from WM6.5. Android concerns me re privacy & I don't like iPhones, so not much choice really! Stuck waiting for MS to provide basic functionality or [worse] a potential need for a future jailbreak to make the thing work properly!
Here's hoping. Many thanks for reading.

First of all, nobody who knew what the hell they were talking about said that WP8 displays as a USB drive (properly called USB Mass Storage). It's an MTP device, like most media players (or indeed WP7, though that had an extra layer of encryption around it). MTP doesn't display the actual filesystem; although the hierarchical display that it presents *may* mirror a real filesystem, it's under no obligation to do so.
The dearth of supported file types in WP7 was a real pain, but it could be fixed by tweaking the registry. In WP8 it's still a pain, but now third-party apps can (officially) register to handle file types. However, as you point out, there's no real way to browse the phone, and the Office hub only shows the filetypes it recognizes. We *might* be able to fix that, if we could get registry write permission, but that's not possible right now. With that said, I don't know if it would be possible for another app to register the (for example) .txt extension; the phone does offer the ability to choose what app opens a given file type.
For what it's worth, Bluetooth file transfer to the phone works fine, and the files will open in whatever app is registered to the file's extension. You can then save them into the app's storage (Documents, for Office apps). This may be a better way to transfer your data.

In WP8 you can build Apps that associate themselves with certain filetypes (identified by the ending). If your App is associated with a certain file type the App can also open files of that type from anywhere on the SD Card.
So for example if you put a *.log file onto the SD Card any App that is associated with the ".log" ending can read it (the Explorer functionality for the SD Card would have to be implemented by the App itself but it is supported). This does not work with the integrated storage though. With integrated storage you would still have to receive it via E-Mail, SkyDrive, etc.
Now for the caveats:
- Apps can't be dynamically associated with File Types. If you want to open "*.log" files the App developer has to associate his App with the filetype in it's manifest. If several Apps exist for a given filetype the user will be asked which one to use.
- There is a quite extensive list of file types that are reserved for the OS or built in Apps. Any file type that is reserved in that way can't be associated with third Party Apps. This contains Office documents (except PDF, TXT files and lots of media file types). The complete list can be seen here: http://msdn.microsoft.com/en-us/library/windowsphone/develop/jj207065(v=vs.105).aspx
- Apps can only read from the SD Card but they can't Change data there.
Now as for your Problem: someone could build an App that supports e.g. Log-Files and you could use your Lumia 820 with an SD Card to pretty much work the way you intend to with those files. It's not really trivial though, given that 10 MB big plain Text-Files regularly lead to Trouble even on PC text Editors (the developer has to be smart on how to handle These "huge" files, so just some midnight hack job won't do).
What are your further requirements? Search pretty obviously. But what are all the filetypes you would need? Would you need editing capability?
Just trying to understand the compelete picture of your requirements. Perhaps you can tell us what kinds of files you use and for what purposes.

Thanks for taking the time to reply.
@GoodDayToDie
Re 'seen as a USB drive' - That's me being careless with words, what I meant to say was the ability to local sync over a USB cable, & then access the copied files on the device. I didn't think that you could do this with WP7 [without frigs], & had high[er] hopes for WP8.
I might have a look at Bluetooth FT as a method for getting the [bulk] data over locally, as I won't be doing it via the cloud [email or Skydrive]. Thanks for the advice.
@StevieBallz
Thanks for the MSDN reference - Very interesting.
Ok, so the apps can potentially access the data on the SD card but not write to it - As an aside, I thought I read something the other day that said data on the SD card was limited to Pictures, Videos, Music etc, as a security measure. That's interesting too then, though anything I want to be 'secure' I'd keep in the internal storage anyway.
Re the comment re 'Trouble even on PC text Editors'. Yes, I tried way back on WM2003 to get a file displayer going, but immediately hit problems with [I think] a 32KB limit on the textbox display. I've just made do with WM6.5's Word displayer since, which offers basic functionality.I keep meaning to go back to the coding, but haven't managed it yet [I think Visual Basic was missing for a while with WP, if indeed it's there yet (I thought I'd read it was with VS2012?)].
Re my 'requirements'. Just to be able to search [large-ish] text files & have the o/p displayed in a manner that's readable [no word-wrapping]. I realise editing is a whole new ball game, so read-only would be good enough. Longer term, I'd like the ability to have many text files open at once - On the desktop I use "Programmer's File Editor", & something like that [if only as a viewer] I'd find invaluable on the smartphone/PDA. I also have many thousands of files on my desktop [PDF, DOC, RTF, HTM, TXT etc] & ideally I'd like access to those on the go as & when needed, via a hierarchical file system on the mobile device, with the structure exactly mirroring the PC's file system, so that I'd search for & find data in the same places regardless of which device I was using [Why thousands? Might be 100s+ actually, & these could be electricity bills, sales receipts, insurance documents - anything - the stuff of life really].
I'll continue with my testing of Office Mobile Word's displaying & searching of text files. I've found it patchy & not consistent so far, but am going to have to move from WM6.5 eventually [more's the pity], & don't really want the hassle of sending the device back again.
Many thanks for your advice so far.

Device returned, many thanks for your help. Maybe WP9 then?

5v17 said:
Device returned, many thanks for your help. Maybe WP9 then?
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Judging by the ideas picked up for review on dev user voice, situation may drastically improve with the next SDK update.

Please share a wp8-compileable SharpFtpServer to me..

I'm recently developing a file explorer for interior unlocked wp8 phones and FTP may be the best way to transfer files via WiFi especially when there are a huge amount of files, FTP is more convenient than Webserver or other ways. However, I learned little knowledge about network so I can do nothing about it because some of the classes are missing and I don't know which to replace with.
There ARE apps in store which uses SharpFTPServer such as Yxplayer so it is possible to port one.
BTW, @GoodDayToDie , do you plan to add FTP support to your Native Access project ?

Wasn't planning to, really, but you have a point about making it easy. HTTP is fine for downloading specific files but isn't actually a very good choice for a file system browser.