deleting snapshots

I am running Parallels desktop 5 in MAC OS X (10.5.8) and running windows XP in the virtual machine. I am trying to get rid of snapshots bit get an error message. In the snapshot manager, the images of the snapshots are all grey. The error message when i click on any of the snapshots is "The configuration file you specified is invalid" "make sure that the specified file is a valid Parallels machine configuration file and it is not corrupt, or select another file". i think the cause of this is that I tried to delete snapshots while my hard drive was fairly full and the process ran out of space and crashed. i have subsequently moved my media folders to an external disk and have freed up lots of space, but still get the error message

I would appreciate any help you can give me

 

Exactly the same problem here - is there no one in the Team who could give an answer ?

 

And the same problem here, in Desktop 7.