Official links sometimes become unavailable. In that case, community‑hosted mirrors are your best bet, but always verify the file’s MD5 hash if possible.
OnePlus occasionally releases "rollback" packages that allow users to revert to previous versions via the stock recovery mode.
If your browser saves this file as LocalUpdate.zip , you must use a file manager application to rename it to LocalUpdate.apk by removing the .zip suffix. 2. Official Android 11 Rollback Firmware
Complete the initial Android setup wizard without signing into Wi-Fi to prevent immediate downloading of updates. downgrade oneplus 9 to android 11 exclusive
Charge your OnePlus 9 to at least to prevent sudden shutdowns.
If local update consistently fails, switch to the MSM Download Tool method described above.
Downgrading your device to a previous version of Android can potentially cause issues with your device's functionality and security. Proceed with caution and at your own risk. Official links sometimes become unavailable
Before proceeding, understand these critical risks:
: If your phone becomes unresponsive or "bricked," you may need to use the MSM Download Tool on a PC to force-flash the original firmware. Verification : After the first boot, go to Settings > About Phone to confirm you are on Android 11. for your region's rollback package? Oneplus 9 Pro | Downgrade to OXYGEN OS 11
Use or the built-in Google backup to save: If your browser saves this file as LocalUpdate
Confirm the installation. The phone will verify the file and then begin the process, which usually takes 5–10 minutes.
Confirm the warning that all data will be erased and click . Finalize the Process : Wait for the installation to reach 100%.
[System Update App] ➔ [Gear Icon] ➔ [Select .zip File] ➔ [Confirm Rollback]
This error often occurs when you are trying to flash a rollback package that does not match your current firmware region or when the local update APK is not properly installed. Double‑check your phone’s exact model number (Settings → About Phone) and download the rollback ZIP that matches it. Also, make sure you are using the correct local update APK for Android 12.