Nexus 6 OTA from 5.0.1 to 5.1 fails - Error in block.map I am trying to upgrade my Nexus 6 with version 5.0.1 (Build number LRX22C) via OTA to Android 5.1.

The OTA update is downloaded successfully and after pressing "Restart &amp; Install" I see a dead droid with the message "Error!".

The phone was rooted and I unrooted it via SuperSU. Did not help.
Wiping cache partition also did not change anything.

These are the logs:

Finding update package..
Opening update package..
Verifying update package..
Installing update..
Verifying current system..
/dev/block/platform/msm_sdcc.1/by-name/system has been remounted R/W: reflash device to reenable OTA updates
E: Error in 0/cache/recovery/block.map
(Status 7)

Installation aborted.


I would really like to upgrade without wiping the data.
Unfortunately it will not work, google checks some files for integrity (meaning: that they were not changed) and it seems that some of the files have been changed, possibly by the  root process.
I assume you have no other option but to install the image manually, which will wipe your phone entirely.
You can learn more about the process here: 
https://developers.google.com/android/nexus/images