[OnePlus 7 Pro Guides, News, & Discussion] Inductive Soul:
Greetings, and a brief disclaimer;

--Disclaimer--

I am not responsible if you lose data or your device grows legs and runs away from you...

by following any of the instructions in this post, you take sole responsibility whatever happens to you or your device and any one else involved.

--Throughout this process we will be continuously wiping the device.--

--This tutorial flashes the International Firmware, you will not be running T-Mobiles Firmware.--

--If you want T-Mobiles Firmware this is not for you.--

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Greetings fellow T-Mobile OnePlus 7 Pro Users and Developers!

I am excited after much frustration and beating my head against the wall, screaming profanities at T-Mobile & OnePlus for locking down this amazing phone.

Me and my Friend have FINALLY found out how to Bootloader Unlock, TWRP and ROOT the OnePlus 7 Pro from T-Mobile!

I know this is a longer guide, but that is because there were quite a few steps for the T-Mobile variant. A few snags were hit with the T-Mobile variant so that's why this guide is so lengthy.

The extra benefit of this guide is:

* You will have the DUAL SIM feature working. - I can confirm as I have placed two SIM's in the device and switched between them, T-Mobile disabled one of the OP 7 Pro SIM Slots, but with the Firmware Flash you get it back, I find that Flashing to International Firmware an important step as your getting a major feature of the device back. --Though you will need to buy a Dual SIM tray if you want to use two SIM's, this is where I bought mine: OnePlus 7 Pro DUAL SIM Tray

* You will get working Sound, if you go straight to Android Q from the flash and install TWRP * Magisk you will have audio issues. - I didn't think to test what else went wrong, but that I know did.

* DRM is working, I can stream Netflix content.

* Audio Fixes and Camera Features appear and sound great.

* I have not had stability issues such as crashes, reboot or other unwanted.

* WiFi, Bluetooth, DUAL GSM Radio's working properly.

* You can switch between the services of both SIM's properly via the pulldown menu, as well you can set up SIM defaults for particular actions.

* T-Mobiles VoLTE is working, as is VoWiFi. - Nice if your like me and live primarily in a basement apartment and get crap signal.

* You will not need to get T-Mobile's stupid Bootloader Unlock Token (BUT), that can take upwards of two weeks to get, to unlock the bootloader with this method. -- Skip the line, Yes please! I like skipping past BUT's.

--What you need to do first!--

You MUST get your phone Permanently CARRIER UNLOCKED

BEFORE

YOU ATTEMPT ANYTHING HERE!!!

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--GUIDE--

1. I applied T-Mobiles: (9.5.9 Security Patch) I saw and installed it on July 23rd 2019 - This was needed in order to get the Flashing tool to work as it would get stuck on Param because without that patch the EDL would not allow the tool to flash the OnePlus 7 Pro.

2. I enabled ADB Debugging and used: TOOL ALL IN ONE to install my OnePlus 7 Pro Drivers, I also enabled Advanced Reboot in Developer Options.

2a. If you don't know how to enable Developer Options or ADB Debugging & Advanced Reboot here is how...

2b. Go into Settings, About Phone, TAP Build Number until it pops up that you are a developer (if you have a password/fingerprint set up it will ask you to put it in.).

2c. Go to Settings, System, Advanced Options, Developer Options.

2d. Enable, Advanced Reboot, USB Debugging.

3. I followed the Tutorial on this link to install the International Firmware (WARNING THIS WILL WIPE YOUR Phones DATA!!!): [GUIDE]How to convert TMobile OP7 to International.

4. I then updated the phone through the phones OTA updater via Settings, System, System Updates all the way until it had no more updates. ( If we installed Android Q before this we found that the speaker had issues during a Google Duo call. So something about how this all stacks and builds up together breaks if you don't do this in order.)

5. We then downloaded and placed: Android Q Beta onto the root of the OnePlus 7 Pro storage.

5a I went to Settings, System, System Update, Options, Local Upgrade.

5b If you have the Android Q firmware in the right place you will get that as an option to flash, once it's done click the button to reboot.

6. Unlocking the Bootloader.

6a. Enable Developer Options.

6b. Now we enable OEM Unlocking, and Advanced Reboot if not already. ( If you did not previously get your device Permanently SIM Unlocked you will not be able to enable OEM Unlocking, and you will be stuck unless you flash back to T-Mobile's Firmware and use their proprietary SIM Unlock APP. ).

6c. Press power button and reboot to Bootloader.

6d. Run the command ( fastboot oem unlock ). It should ask you on the phones screen if you want to, say yes.

6e. Run the command ( fastboot oem device-info ). Check to see if the bootloader unlock is True or False, True is expected. If False unlock the bootloader via other methods.

7. Booting TWRP & Flashing TWIRP + Magisk.

This was a bit tricky as the existing tutorials did not work with my device and I had to add a step.

First get the TWRP.IMG & TWRP Installer ZIP files ready as well grab Magisk by downloading them here: Official/Unofficial TWRP recovery for OnePlus 7 Pro. & Magisk

7a. Run the command ( fastboot boot TWRP.IMG ) The phone should then boot into what looks like full TWRP, well sorta, it's not really installed yet.

7b. If 7a fails as it did with me Run the Command ( fastboot set_active b ) then try 7a command again, if that fails as well run ( fastboot set_active a ). and repeat.

7c. Once you have booted TWRP put the TWRP installer ZIP on the phone in the root directory.

7d. Now we get the Magisk installer zip on the root of the phone as well.

7e. Now we install TWRP installer ZIP first then Magisk installer ZIP.

Reboot - Enjoy and install custom ROMs & Kernels!