Repairing non-booting Windows 2012 R2 and others
If you're stuck in a "Preparing Automatic Repair" boot loop that always takes you back to the blue screen of unhelpful menu options: Disable Automatic repair Get to the recovery command prompt bcdedit /enum Get the name of the Windows entry (likely to be {default} bcdedit /set {default} recoveryenabled No Reboot Now instead of getting into the loop of a failing repair it'll show you the real problem that it's failing to fix. This is likely to be a corrupt file. In my case it was c:\windows\system32\drivers\cng.sys which I copied from a working server that was at the same patch level.