I have a MacBook Pro (software Mac OS X Lion 10.7.5). I haven't had any problems in the past backing-up to my Time Machine and now I am getting this message:
Time Machine could not complete the backup.
The backup disk image"/Volumes/Name's Time Caps/Name's MacBook Pro sparsebundle" is already in use.
TM is the worst backup App I've ever seen, thankfully we have the wonderful podini enumerating all it's failings...
Retrieving data ...