Cyanogenmod: Encryption unsuccessful I encrypted my phone. That worked fine. Then I installed another version of Cyanogenmod. This cannot decrypt the data (which is OK: There is no important data on the phone). It tells me to perform a factory reset, but even after the factory reset the phone is stuck at the "Encryption unsuccessful".

The error I get is the same as on:
Samsung Galaxy encryption failed

How do I convince Cyanogenmod that all encrypted data is deleted?

I have tried:


Factory reset
Installing the version of Cyanogenmod that encrypted the phone
The factory reset failed to format /data (and thus most likely left the old encryption in place).

Having formatted /data manually, the factory reset finally could complete successfully, and the new version of Cyanogenmod showed up.