SBS 2003 NT-Backup failure

Hello everyone, have been having an issue with my SBS 2003 backup. I'm really stumped and have no idea what to do

Here is the Log

Backup Status
Operation: Backup
Active backup destination: File
Media name: "Backup.bkf created 14/12/2012 at 9:02 AM"

Volume shadow copy creation: Attempt 1.

Error returned while creating the volume shadow copy:0x80070057.

Error returned while creating the volume shadow copy:The parameter is incorrect.


Aborting Backup.

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The operation did not successfully complete.

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Regards Eli Ailakis