I have opened the following preference files:
None of them mention the volume being used for time machine backups. Any ideas?
Time Machine's main preferences can be found at
The Backup hard drive is actually stored as an data blob(1) under the key
1 - This is the base64 decoded form of a _CFULRAlias to be exact.
Ho 5y old topic ;) however you can simply delete /Library/Preferences/com.apple.TimeMachine.plist file and add your TM drive back again in TM settings panel. Works for me.