The only reference to that error that I see in this system is when you specify an incorrect encryption password. And that error was reported in the 7.0 release and subsequently fixed to bring up the encryption password dialog again rather than throw that generic error. Can you confirm what version of the product are using, whether this is a legacy or new backup format virtual machine backup, and whether or not you are using encryption and, if so, whether or not it's possible you specified and incorrect password at restored time?

Based on your feedback I upgraded from 7.4.22 and it's now working properly. For reference I had the correct encryption password because it's working now with the exact same password and it was also doing the same thing before on unencrypted backups.

Thanks,

Glad you're up and running. Let us know if you have any further questions.