If you installed the recently launched Android P developer preview 1 on your Pixel device, you might have already got in touch with the new features that the new OS offers. However, since this is the first preview version of the Android P, it might be unstable. So if you prefer Android Oreo afore the Android P, then this guide is for you.
Check the step-by-step guide given below to downgrade your Pixel back to Oreo from Android P. Downgrading from Android P to Oreo isn’t as simple as we think. It requires flashing factory images on to the device via fastboot. The process may take long time to complete (more than 30 minutes). Also, the process will wipe data from the device, so you need to back up every important data you have on the phone before proceeding.
To downgrade Pixel devices from Android P, following things are needed:
– ADB and fastboot driver setup on the PC (refer this or this guide)
– Unlocked bootloader (see below)
How to downgrade Pixel back to Android Oreo
1. Download Oreo factory image for your device from Google here.
2. Unzip the downloaded zip file using app like 7zip.
3. Save the unzipped files into the same folder as ADB is installed on your PC.
4. Enable “USB Debugging” and “OEM Unlock” on your device from Developer options menu.
5. Connect your device to your PC, go to ADB installation folder and open a command window from there (shift key + right click and select open command window here option).
6. Now boot your device into fastboot mode. To do so, in the command prompt, type the below command and hit enter:
adb reboot bootloader
How to unlock the bootloader
If you have not unlocked the bootloader, then you need to unlock it first. This will ERASE your device, so make sure you have backed everything up first and then proceed with below steps.
In the command prompt, type fastboot flashing unlock and press enter key.
On your phone, choose “Yes” (use volume key) and confirm it by pressing the Power button. With the bootloader unlocked, you can install the Android Oreo firmware.
How to flash factory image
Go to the ADB folder (where you have saved the unzipped factory image) and execute the flash-all script. This script installs the necessary bootloader, baseband firmware(s), and operating system.
On Windows: Run the file “flash-all.bat”.
On Mac: Run the file “flash-all.sh” using Terminal.
On Linux: Run the file “flash-all.sh”.
IMPORTANT: You will see some ‘not found’ messages on command prompt. Do not do anything. Wait for the process to complete. The phone will reboot automatically.
You have now successfully downgraded your device from Android P. In certain situations ‘flash-all-script’ won’t work. In such situation you can flash individual files (boot image, bootloader, radio, recovery, system, and vendor image) manually.
– To do so, first flash the botloader image. In the command prompt type the command given below and hit enter:
fastboot flash bootloader File name for bootloader.img
[File name for bootloader.img= replace with original file name]
– Once done, type the command fastboot reboot-bootloader and hit enter. This is important!
– Now flash boot image, radio image, recovery image, system image, vendor image respectively.
– Finally type the command fastboot reboot to reboot your device. That’s it!
When the process finished, you should lock the bootloader again for security. For that, boot your device into fastboot mode again, and then issue the command: fastboot flashing lock.
This can take a few minutes to complete, but once it does, your device should reboot automatically, running stock firmware.
