Hi robrer,
I’d suggest you to perform clean boot and check if the error message still appears during backup. If you don’t get error message after doing clean boot, one of startup programs or services running when your computer starts is causing this issue.
Visit the link below for steps to perform Advanced Troubleshooting using clean boot,
http://support.microsoft.com/default.aspx/kb/929135
Follow the steps below to perform clean boot.
1. Click Start, type msconfig in the Start Search box, and then press ENTER.
2. If you are prompted for an administrator password or for a confirmation, type the password, or click Continue.
3. On the General tab, click Selective Startup.
4. Under Selective Startup, click to clear the Load Startup Items check box.
5. Click the Services tab, click to select the Hide All Microsoft Services check box, and then click Disable All.
6. Click OK.
7. When you are prompted, click Restart.
To undo the changes and start your computer normally, please see the steps described below,
1. Click Start, type msconfig.exe in the Start Search box, and then press ENTER.
2. On the General tab, click the Normal Startup option, and then click OK.
3. When you are prompted to restart the computer, click Restart.
Please check in Event viewer for the cause of this error message, if the above method does not help. Visit the link below how to use Event Viewer to check for information about the error message you’re getting.
http://windows.microsoft.com/en-us/windows7/What-information-appears-in-event-logs-Event-Viewer
Hope this information helps!
Yaaser - Microsoft Support Engineer
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