How to Covert T-Mobile One Plus 7T to the International Version

I shattered my phone screen several days ago, and decided to move my stuff from ios to Android, due to the huge price difference. Eventually, I managed to get an unlocked T-Mobile OnePlus 7T from B&H at about 300$. The phone is unlocked, but the system is the T-Mobile version, meaning all updates would be released from T-Mobile after a delay and the start screen will have a huge T-Mobile logo.

To get rid all of these, I flashed my system into the international version system, following this guide. Yet, as this is my first time dealing with Android, I met some problems, and the whole process toke me about three whole hours, motivating me to add some notes to the original guide.

1. First step

Download the patched MSM download tool: https://drive.google.com/file/d/12y3lO0wIgb2_LSDeVw9x_2C_HjbgZlb_/view?usp=sharing

An easy first step.

2. Second step

Run the tool, connect your phone in EDL mode (see below how to do it if you don’t know), ensure the “sha256 check” is NOT checked, click the Start button and wait until it’s completed.

The second is not that easy. To get through, you need to:

• Install the Qualcomm HS-USB QDLoader 9008 Driver (device manager -> find the phone in other devices -> update driver -> install the optional windows update)
• To enter the EDL mode:

  power off the phone and disconnect the USB if it’s connected. Then press both volume UP and DOWN at same time, then while holding those buttons down, insert the USB which should already be connected to your computer.

• If you decide to quit, you can download a different MSM tool to revert the system back to the T-Mobile system

3. Third Step

The phone will show a red warning saying “device is corrupt”, just ignore that and wait some time. It will fallback in fastboot because it’s not able to boot. Update your fastboot executable, otherwise you’ll encounter errors and modem issues. Download it here: https://dl.google.com/android/repository/platform-tools-latest-windows.zip. Now run the following fastboot command fastboot flashing unlock_critical.

I changed the order of this part a little bit. It is necessary to download the Android Usb Driver, and install the driver via the step 39+ in this guide. In the end, a selection UI will be available (volume up/down, and power for operation).

4. Fourth Step

Bootloader is now unlocked.

Finally!

5. Fifth Step

Extract the contents of the Global Fastboot Rom zip folder directly into your ADB folder.

• If you did this correctly your ADB folder will be filled with a bunch of new .img files. Like boot.img​ Open CMD (with admin rights) and navigate to your ADB folder. run flash-all.bat (on PC).

I recommend to install an Not-Up-To-Date version here, and then update later. In my case, I need to repeat this process twice. After the first time, T-Mobile logo will still show up, and the wifi is not available. I entered the system, go to setting, first go to About 7T and tap … three times to enable developer mode, then go to … and turn on advanced boot choice and reboot into fastboot again. Re-flash the system with flash-all.bat again. now it would have the choice to select language after roboot, but DO NOTHING HERE!

6. Final Step

You’ve now fully converted to the Global Firmware. Confirm this by going to settings > about phone and look at Build Number. Update the system to the latest firmwarm. Lock the bootloader again by first entering the fastboot, then check to make sure phone is being picked up by bootloader via fastboot devices (on PC), and finally relock bootloader via fastboot oem lock (on PC).

Welcome to the international version OnePlus 7T!