: Download the official OxygenOS 11 zip for your model from the OnePlus Community Support : If the file ends in , rename it to end in using your file manager. Local Update APK : Download the Official OnePlus Local Update Tool : If the APK download ends in , rename it to to install it. Step 2: Prepare the Installation Move the Rollback Zip : Move the downloaded OxygenOS 11 zip file to the Root Directory
, as the built-in update tool often hides the "Local install" option on newer OxygenOS versions. OnePlus Community ⚠️ Critical Warning : This process will completely wipe Downgrade Oneplus 9 To Android 11
If you try to load an Android 11 zip file via Local Upgrade on an Android 12/13 device, the system will typically reject it or force a data wipe : Download the official OxygenOS 11 zip for
If Method 1 fails (e.g., the phone shows "Verification failed"), or if your phone is stuck in a boot loop, you need the MSM Tool. This flashes the factory firmware directly to the hardware. OnePlus Community ⚠️ Critical Warning : This process
On your PC, install the Qualcomm HS-USB QDLoader 9008 drivers. Without these, the PC won't see your phone.
This will wipe your phone and relock the bootloader if it was unlocked.
