[Guide] De-branding AT&T Nokia Lumia 635/**820**

[Fernando Cabrera]

Can't change 820 AT&T rom whit this tutorial, and any tutorial, its impossible.

 

[pankaj981]

Can't change 820 AT&T rom whit this tutorial, and any tutorial, its impossible.

What error/issue are you having?

 

[Fernando Cabrera]

What error/issue are you having?

"The FFU file is not meant for this product. The platform ID of image does not match with platform ID of the device."

 

[pankaj981]

"The FFU file is not meant for this product. The platform ID of image does not match with platform ID of the device."

Are you using the Product Support Tool and getting that error?

 

[nCogNeato]

Thanks a lot for that guide!!!

After many failures with other Tut's I finally managed to debrand my ATT Lumia 635. Without the ATT lock I also managed to flash a RM-974 ROM on the RM-975 origin after debranding the device. Everything's OK.

Looking forward trying to debrand my new Lumia 640 LTE ATT GoPhone when it arrives.

THX once more!!!

Let us know how it goes. I also have a 640 I'd like to de-brand, but haven't seen a successful attempt yet.

 

[PepperdotNet]

The basic premise of this is changing the product code of an AT&T device so that it finds and downloads a newer firmware for a non-AT&T product code. If there's no newer firmware available you are stuck. Depending on how long the phone has been available, you could flash it to the oldest proper AT&T firmware, do the registry fix to change the product code, and then do the OTA upgrade. If that is successful, you can then explore doing a direct flash with a non-AT&T firmware. To flash a device with a different product code you need something more flexible than the recovery tool.

 

[phil2991]

Can anyone tell me how to change my Lumia 635 back to AT&T firmware after following this debranding tutorial? I would like to get my phone back to a state where I can use the Windows Device Recovery Tool again....

 

[pankaj981]

Can anyone tell me how to change my Lumia 635 back to AT&T firmware after following this debranding tutorial? I would like to get my phone back to a state where I can use the Windows Device Recovery Tool again....

I haven't personally tried this but I believe the old Lumia Software Recovery does revert back to the original ROM (check this thread)


Download link: http://go.microsoft.com/fwlink/?LinkID=525568

 

[phil2991]

Unfortunately, that did not work. It said I need to use the new Windows Device Recovery Tool... Its too bad that there is not a way to just manually flash the AT&T firmware onto the phone.

 

[PepperdotNet]

The way to do it, and I don't know whether it would work or not, would be to flash the phone to an earlier version of the unbranded ROM you have it on now, then use the registry trick to change it back into the appropriate AT&T device, then let it update OTA. Basically the reversal of the unbranding process.

 

[pankaj981]

Does WDRT give you an FFU error?
Or try changing the registry back to the AT&T postpaid 635 which has a newer firmware and it should overwrite it.

 

[phil2991]

I manually flashed the T-Mobile ffu (059V6W5) - I made sure not to have any type of data or wifi connection so the update would not download until I performed the registry trick. Once I completed the registry trick (switched back to ATT-US and RM-975_1005), I checked for updates, and let it install. Upon rebooting the phone is still on T-Mobile firmware...

 

[phil2991]

Yes, WDRT is giving me the FFU error...

 

[Fernando Cabrera]

Are you using the Product Support Tool and getting that error?

Yes.

 

[PepperdotNet]

It is quite possible that this is a one way trip.

 

[xiForza5]

Hi have the Lumia 635 ATT i already unbranded it few month ago...As far i understand this is what i need to take it back to 8.1 and then download the latest Windows 10 build?

 

[pankaj981]

Thar's Navifirm. It doesn't have the tools to flash the phone. You would need the Product Support Tool to perform the flash.

 

[Fernando Cabrera]

Yes.

What can I do?

 

[pankaj981]

I manually flashed the T-Mobile ffu (059V6W5) - I made sure not to have any type of data or wifi connection so the update would not download until I performed the registry trick. Once I completed the registry trick (switched back to ATT-US and RM-975_1005), I checked for updates, and let it install. Upon rebooting the phone is still on T-Mobile firmware...

AT&T is RM-975_1035, try it.

What can I do?

Are you trying to go back to AT&T firmware?

 

[Xanthurum]

Hey everybody!

Yesterday I tried to debrand my 640 LTE ATT GoPhone. (reset protection OFF)

RM-1073_1044 -> RM-1072_1052
ATT... -> 000-AT

Unfortunatly it didn't work with that trick! (on the 635 it did)
All steps in the procedure work except the last on: searching for updates...
Phone respondes with "up to date".

But I will continue watching this in the future. Maybe someone else got lucky on debranding the 640 and will share his knowledge/steps.

By the way: I'm wondering if it would be possible to just turn off that ATT logo at bootup with this handy registry editor from the tutorial since the phone working properly here in Austria on all GSM-bands... (after unlocking). Uninstalling the ATT stuff manually isn't really a lot of work so I could live with that.
Any ideas?

Cheers