Hi,
reason 5 points to VSS issues on the client. Can you check the event log on the client for more details?
Is there enough free disk space on the client partitions?
Did you run chkdsk /r on the new client against the volume, on which backup fails?
Which operating system are you running there? If Windows 7, would excluding the 100 MB partition from backup fix the issue?
Sometimes also 3rd party applications or their remains in the registry after uninstall (or in your case after moving settings?) like Norton Ghost may cause VSS to fail.
Best greetings from Germany
Olaf