Having trouble backing up with the above error
There is a free scan and cure for this problem on Wikki error site ,has anybody used it
and does it do the job
Although it's referring to updating, rather than to backing up, the Microsoft website suggests that the problem is related to a conflict with your security software:
http://support.microsoft.com/kb/883825
The obvious solution would seem to be to temporarily disable your security software during the back-up process.