Apologies for my ineptitude... I find myself in the very same situation as tdp1947, with the same error message.
Tried running the restore from the command line, I could see some process got to 100%, and then the 'dos window' closed and nothing else happened.
So I tried restoring from inside calibre, and got the usual error message.
The problem is I don't know how to fix the permissions on my calibre library, which is what our master and guru was suggesting.
...and I am the one and only administrator of my PC.
Help, please!
