Yeah, that’s a little problematic; however, once you become a basic user that restriction is lifted, I believe.
This is probably obvious, but it is having trouble mapping the C: drive; are you backing up more than just Leslies-Laptop?
If you are, and are not having any trouble with any of your other clients then it’s a client-side issue; things like your service isn’t running; something isn’t up to date; 8dot3 names (although I think that really only affects UrBackup Windows Servers).
Uroni could probably help more, but you may want to follow this: