Backup keeps failing : Error 0x81000033

Hi,

If you have any security software installed on the computer it would take longer for the backup center to backup files. Try to disable security software and try to take a backup and verify.

If that works fine later enable the security software.

Follow the link for more information

http://windows.microsoft.com/en-US/windows7/Disable-antivirus-software

You may also run disk cleanup utility and check if that helps.

Start Disk Cleanup

http://windows.microsoft.com/en-US/windows7/Start-Disk-Cleanup

Also try to run a Check disk for the hard drive.

To run Check disk

1.       Open Computer by clicking the Start button, and then clicking Computer.

2.       Right-click the hard disk drive that you want to check, and then click Properties.

3.       Click the Tools tab, and then, under Error-checking, click Check Now. If you are prompted for an administrator password or confirmation, type the password or provide confirmation.

To automatically repair problems with files and folders that the scan detects, select Automatically fix file system errors. Otherwise, the disk check will simply report problems but not fix them.

To perform a thorough disk check, select Scan for and attempt recovery of bad sectors. This scan attempts to find and repair physical errors on the hard disk itself, and it can take much longer to complete.

To check for both file errors and physical errors, select both Automatically fix file system errors and Scan for and attempt recovery of bad sectors.

4.       Click Start.

Depending upon the size of your hard disk, this may take several minutes. For best results, don't use your computer for any other tasks while it's checking for errors.

For information follow the link

http://windows.microsoft.com/en-US/windows7/Check-a-drive-for-errors 

After you perform a check disk try running the backup process and check if that helps

Hope this information is helpful.

Amrita M

Microsoft Answers Support Engineer

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