You are probably taking a System State backup of a remote server.

If so, your problem is likely with the shadow copy service on the REMOTE machine.

Perform the Following Steps

1) From a command line; net stop vss (or stop Volume Shadow Copy service from the services applet)

2) Then register the following DLLs and services (be sure you're in
the WINDOWS\system32 directory at your command prompt):

regsvr32 ole32.dll
regsvr32 vss_ps.dll
Vssvc /Register
regsvr32 /i swprv.dll
regsvr32 /i eventcls.dll
regsvr32 es.dll
regsvr32 stdprov.dll
regsvr32 vssui.dll
regsvr32 msxml.dll
regsvr32 msxml3.dll
regsvr32 msxml4.dll

3) Start the Volume Shadow Copy service by running "net start vss" or using the services applet.

4) Reboot the Server