Mac – Is the new Time Machine backup okay if the MacBook went to sleep during encryption

Have a look here and try doing what he does (I know the problem is different).

The key came from a comment buried down near the bottom of the page. Running fsck kept getting clobbered with a "Disk In Use" error, but this solved it:

FWIW, I found that even with -noautofsck, snow leopard would auto-fsck, meaning I would get ‘resource busy’ or whatever. I have no idea why it is ignoring my no-auto-fsck request. Whatever.

To allow the process to go, I ‘ps auxwww | grep fsck’ to find the PID, then ‘sudo kill (PID)’ to kill this fsck so I can run my own.

Killing the auto-fsck allowed me to run it myself. Not sure how long it took, I started it at 2am and it was done by the time I got up 6 hours later, but it was on a 500+ GB .sparsebundle, so I'm assuming it took a while.

Aborting a backup like that sometimes has unfortunate consequences. If this is your initial backup, consider erasing the backup drive and starting over before you go to sleep. That way, the drive can run overnight without you having to worry about leaving before it's finished.

Also make sure that the drive is correctly formatted as as HFS+ extended journaled, with a GUID partitioning scheme.