Flasing Custom ROMs on Oneplus 10R & Ace

If you have OnePlus Ace with OxygenOS installed, you need to follow the below mentioned steps before you flash the custom ROM.

If you have OxygenOS 14/13, then you need to rollback to OxyegnOS 12 and switch back to ColorOS 12.
Download OOS rollback zip from the support chat's notes.
Once you are on OOS12, download COS12 zip from here and to switch to ColorOS, follow this instruction | Video Tutorial
After you have installed ColorOS 12 then lock the bootloader.
Update to the latest ColorOS 14 and unlock bootloader again.
Now you have a fully working bootloader.

All necessary instructions and files can be found in the group OnePlus 10R/ACE

The latest OxygenOS 14 firmware CPH2423/CPH2411 14.0.0.640(EX01) or above installed.

Make sure you have removed your google account & PIN/password.

Download Google's platform-tools, extract it in C drive.
Enable OEM Unlocking & UBB debugging from phone's developers options.
Connect your device to PC, and open cmd in the platform tools folder by typing cmd in the address bar.
Run the following command and approve USB debugging prompt on your device. [If you are not getting an output then update your adb drivers]
adb devices
Run the below command to boot your phone into fastboot mode. After running the command you'll see a black screen with fastboot mode written in very small font.
adb reboot bootloader
Run the below command to check if your device is getting detected in fastboot mode or not.
fastboot devices
If the command is not giving any output/ is waiting for device then you need to update your fastboot drivers
Run the below command to unlock the bootloader.
fastboot flashing unlock
Run the below command to reboot your device after unlocking
fastboot reboot
Setup the device and perform the above Step2 again.

Let's start

Unlocked bootloader and USB debugging enabled from the developer options.
latest ROM.zip, boot.img, dtbo.img, vendor_boot.img for 10R/Ace available here.

Make sure you have removed your google account & PIN/password.

Reboot to bootloader
adb reboot bootloader
Flash LineageOS recovery
fastboot flash --slot=all boot boot.img
fastboot flash --slot=all dtbo dtbo.img
fastboot flash --slot=all vendor_boot vendor_boot.img
Reboot to recovery
fastboot reboot recovery
Skip this if you are dirty flashing. Do a factory reset: Factory Reset > Format data / factory reset
Sideload the LineageOS.zip package: (Apply Update -> Apply from ADB) adb sideload lineage-packagename.zip
Reboot to System

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