Convert T-Mobile to International (with Bootloader Re-LOCK)

[thattechguy_69]

The required files will be attached in the end of this guide.
OnePlus 8 TMobile to Global Fastboot ROM
MSM TOOL for IN2017

Alternatives from the files above, if you get errors every time you are trying to flash like "NO SIM INSTALLED"
(THIS IS WHAT I PERSONALLY USE):
MSM TOOL for IN2017 Alternative
OnePlus 8 Fastboot ROM Alternative

1st Step: (Make sure Test Mode is ON and Driver Signature is OFF)
First install the Drivers of the phone and the Qualcomm Drivers inside the DRIVERS.zip attached to this thread.

2nd Step: Make sure your OnePlus 8 IN2017's bootloader is unlocked- unlocking bootloader will result to factory resetting your phone. Please backup your phone before doing this process. Instructions on how to unlock

3rd Step: After the bootloader is unlocked, you have to enable "USB Debugging" and reboot your device to Fastboot Mode.

4th and Last Step: Unzip the ZIP file and Open the Global Rom (10.5.12 OnePlus 8 Global Rom). Find flash-all.bat and double click on it. Type and enter Y when it asks to and just let it do its Terminal Process.

**After the batch file is done, your phone should automatically boot to Global Rom Oxygen OS and no more of that T-Mobile
splash screen.

This is a YouTube walkthrough video on how to do it: Credits to Fizzy Apps on YouTube

DO NOT LOCK YOUR BOOTLOADER YET, TO LOCK BOOTLOADER (THIS WILL WIPE EVERYTHING):
-Download the latest OxygenOS 11 ROM
-Move the downloaded ROM from "Downloads" folder to "Internal Storage"
-Go to settings and find System Update, then press Local Update and choose the downloaded ROM
-After its done installing, click REBOOT/Restart the device
-After rebooting, go into FASTBOOT MODE and when you are in FASTBOOT MODE, type "fastboot oem lock"
-Press the volume buttons to select LOCK BOOTLOADER and there you go, LOCKED Bootloader!

IF SOMEHOW YOU GOT "QUALCOMM CrashDump Mode" during the 4th step or you locked Bootloader right after flashing ROM and it got corrupted.

1) Enable Test Mode and Disable Driver Signature Verification on Windows PC.

2) On your phone, simultaneously press and hold Volume Up (+) and Power Button and when the screen shuts down, IMMEDIATELY release both buttons. This means you forced shutdown the device.

3) Set year date on your PC to 2017 and Turn off WIFI for MSM Tool to work and after doing this, open MSM TOOL folder you downloaded at the top of this guide and click MsmDownloadTool V4.0.exe

4) On Login, set user type to "OTHER" and click next. at the top left side find "TARGET" and set it to O2/TMO

5) While simultaneously holding both the volume buttons, connect the phone to the PC. As soon as the phone is connected, a COM# like COM3, etc. will appear on the MSM Tool and immediately click ENUM, then click COM#, then Start. (If COM# doesn't show up just continue to click the ENUM button during process and it should show up)

<A YouTube Video walkthrough of this process> Credits to Shahin Shaan for this.

**This should start the process of restoring your phone back to OxygenOS 10 and you have to start back to square 1 in order to flash Global ROM again. So, USB Debugging>Fastboot Mode>Unlock Bootloader>Enable USB Debugging Again>Boot again to Fastboot>Double Click on flash-all.bat on Global ROM folder. Also, I added TOOL ALL IN ONE which should make unlocking bootloader, booting to Fastboot faster.



Credits to these amazing people for making this possible:

•@matteosaeed and his Guide.
•Ms. user_ajusee's Guide
•Mr. gregoryaul (@Aulgreg38) from HighOnAndroid Forums
•THE MAN HIMSELF: Mr. Max Lee himself of HighOnAndroid Forums; link to his YouTube channel.

 

[Aulgreg38]

Thanks thattechguy_69 for the shout out much appreciate that, just glad I was able to help

 

[thattechguy_69]

UPDATE: 04/10/2022
IF THE MSM TOOL THAT I PROVIDED DOESN'T WORK TRY THIS VERSION OF MSM TOOL AND EURO FASTBOOT ROM. THEN JUST FOLLOW THE GUIDE ON THE END OF THIS THREAD TO GO TO GLOBAL
MSMTool
OnePlus 8 Euro ROM
(In my status of converting using 10.5.7, I cannot get a working SIM Signal and It keeps rebooting the phone. So if you have problems similar to this, just use these versions because these have worked for me so far.)

UPDATE 11-21-2021:
LOCKED BOOTLOADER SCREENSHOTS*

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[thattechguy_69]

Thanks thattechguy_69 for the shout out much appreciate that, just glad I was able to help

Oh thank you Mister!

 

[Adriancris7]

Hi man i do everthing like the post say and i got it. But i notices that when you convert t-mobile oneplus 8 to global you lose safetynet. so i was wondering 2 things. How can i get safetynet working again, and if i relock the bootloader with the global firmware will it boot or it will break? Thanks mate.

 

[thattechguy_69]

Hi man i do everthing like the post say and i got it. But i notices that when you convert t-mobile oneplus 8 to global you lose safetynet. so i was wondering 2 things. How can i get safetynet working again, and if i relock the bootloader with the global firmware will it boot or it will break? Thanks mate.

If you lock bootloader the system will say your phone has been corrupted and if you did happened to lock your bootloader. You are gonna have to use MSM tool to restore OS and your are gonna have to start again to step 1.

For the other issue which is safetynet, did you root your phone? From what I know you would only lose your safety net when you root your phone. I did root my phone 2 weeks ago and from what I remember my safetynet was fine. You are gonna have to ask someone about safety net man since I am no expert at that region.

Anyways, thank you for using this guide. Really appreciate it man

 

[Adriancris7]

If you lock bootloader the system will say your phone has been corrupted and if you did happened to lock your bootloader. You are gonna have to use MSM tool to restore OS and your are gonna have to start again to step 1.

For the other issue which is safetynet, did you root your phone? From what I know you would only lose your safety net when you root your phone. I did root my phone 2 weeks ago and from what I remember my safetynet was fine. You are gonna have to ask someone about safety net man since I am no expert at that region.

Anyways, thank you for using this guide. Really appreciate it man

Ok, I see.. I didn't root the phone. I just want to know. It's just I try to install Netflix in play store and the app didn't show.... So I install safetynet test and shows that it's not working... I don't have plane to root the phone. I only want to convert the phone to global... I don't know how to solve the issue of safetynet.. that why I ask you. Anyway the phone is working flawless no issue at all.

 

[thattechguy_69]

Ok, I see.. I didn't root the phone. I just want to know. It's just I try to install Netflix in play store and the app didn't show.... So I install safetynet test and shows that it's not working... I don't have plane to root the phone. I only want to convert the phone to global... I don't know how to solve the issue of safetynet.. that why I ask you. Anyway the phone is working flawless no issue at all.

Ok so I check my Play Store Certification and I just found out that my device has not been certified which means that's the reason why you couldnt install/update Netflix.

 

[Adriancris7]

Ok so I check my Play Store Certification and I just found out that my device has not been certified which means that's the reason why you couldnt install/update Netflix.

Yeah, that's what I told you. How can we solve the issue. It's the only bug I've found.

 

[thattechguy_69]

Yeah, that's what I told you. How can we solve the issue. It's the only bug I've found.

Download "Device ID" and copy Google Service Framework (GSF) and then paste it on this link
https://www.google.com/android/uncertified/ , just wait for Google to Verify your device. If it does not work then just download apk on apkmirror or revert back to T-Mobile ROM. I am in the process of trying to get mine also certified.

 

[Oneplus8rooter]

This worked for me, but had the same issue with the safetynet and thus can't use google pay. Just submitted the GSF for google to verify. Did google verified your device yet?

 

[thattechguy_69]

This worked for me, but had the same issue with the safetynet and thus can't use google pay. Just submitted the GSF for google to verify. Did google verified your device yet?

I changed my ROM to Pixel Experience because of OOS 11 battery issues and etc. But I dont think it did certify my device. Did some research on this before I switch and someone said it should certify your device but it wont say it. Another method I heard is to clear cache and storage cache on Play Store App and it should but I have never tested this one. The most sure method I saw was to root phone and bypass.

 

[Oneplus8rooter]

I changed my ROM to Pixel Experience because of OOS 11 battery issues and etc. But I dont think it did certify my device. Did some research on this before I switch and someone said it should certify your device but it wont say it. Another method I heard is to clear cache and storage cache on Play Store App and it should but I have never tested this one. The most sure method I saw was to root phone and bypass.

Yeah, I tried the play store app and gpay cache and storage cache clearing with no luck. I use gpay with NFC quite often so it was a bummer that it won't work without being certified. Thanks you for writing the guide regardless!

 

[thattechguy_69]

Yeah, I tried the play store app and gpay cache and storage cache clearing with no luck. I use gpay with NFC quite often so it was a bummer that it won't work without being certified. Thanks you for writing the guide regardless!

So sorry man. Thanks for letting me know it worked tho! You should try pixel experience tho. It is certified

 

[Oneplus8rooter]

So sorry man. Thanks for letting me know it worked tho! You should try pixel experience tho. It is certified

Yeah, everything else seems to work well besides that.

As much as I would like to try the other ROM, do they keep up with security patches? I just bought this phone used (Tmobile unlocked) and haven't rooted an android for a while and wasn't sure if they still get updates directly from google or some volunteer is maintaining the ROM. Would like to root it to whatever ROM that is the most maintenance free and would support security updates at least for a couple of years. I think oneplus support it up to 2023 for oneplus 8 if I'm not wrong.

 

[thattechguy_69]

Yeah, everything else seems to work well besides that.

As much as I would like to try the other ROM, do they keep up with security patches? I just bought this phone used (Tmobile unlocked) and haven't rooted an android for a while and wasn't sure if they still get updates directly from google or some volunteer is maintaining the ROM. Would like to root it to whatever ROM that is the most maintenance free and would support security updates at least for a couple of years. I think oneplus support it up to 2023 for oneplus 8 if I'm not wrong.

Yes they do keep up with updates but the people that are maintaing it are not from google. But I will assure you that it is way smoother and more optimized that the current oos 11. I also bought my phone recently 1 month ago as used! You can check some youtube channels if you are interested in pixel experience. Also changing rom does not require root so you dont have to tinker with safetynet and stuff

 

[Oneplus8rooter]

Yes they do keep up with updates but the people that are maintaing it are not from google. But I will assure you that it is way smoother and more optimized that the current oos 11. I also bought my phone recently 1 month ago as used! You can check some youtube channels if you are interested in pixel experience. Also changing rom does not require root so you dont have to tinker with safetynet and stuff

Wow, that looks really good. I might just try that out instead of going back to t mobile stock. Thank you!!

 

[thattechguy_69]

Wow, that looks really good. I might just try that out instead of going back to t mobile stock. Thank you!!

Here are the instructions and Follow THE GUIDE AND I MEAN IT: https://wiki.pixelexperience.org/devices/instantnoodlep/install/

you have to be in the latest oos 11 and in the last part of the guide, you can lock back the bootloader by replacing avb key with a custom one. If you dont update to the latest. It will keep saying system ui not working. Learned it the hard way and was hard stuck for 3 days lol. The os itself is directly from the pixels but with added features that was unique from oxygen os so google will think you have a pixel.

 

[Oneplus8rooter]

Here are the instructions and Follow THE GUIDE AND I MEAN IT: https://wiki.pixelexperience.org/devices/instantnoodlep/install/

you have to be in the latest oos 11 and in the last part of the guide, you can lock back the bootloader by replacing avb key with a custom one. If you dont update to the latest. It will keep saying system ui not working. Learned it the hard way and was hard stuck for 3 days lol. The os itself is directly from the pixels but with added features that was unique from oxygen os so google will think you have a pixel.

You are a godsend sir!! Looks like I'll be tinkering with it tonight! Thank you so much!

 

[thattechguy_69]

You are a godsend sir!! Looks like I'll be tinkering with it tonight! Thank you so much!

No problem!!! Just love helping people i am too young to be called sir im 15 please, call me Aaron!