How to update Lollipop (Android 5.0) on a rooted nexus device

On a rooted nexus device with Lollipop (Android 5.0) the common OTA-updates fails. The reason is: there are some additional security checks while the OTA-update, which fails on rooted devices.

But if you know how to handle the adb-tools, it’s easy to make a manually update. Just download the matching  factory image for your android device and extract the following files: boot.img, recovery.img and system.img.

adb reboot bootloader
fastboot flash system system.img
fastboot flash boot boot.img
fastboot flash recovery recovery.img
fastboot format cache
fastboot reboot

That’s it! All your private files won’t be deleted.

I’ve tested it with my nexus 10 and I couldn’t guarantee that this is true for other devices.