seenuguddu,
Have you recently installed any Norton/Symantec software or possibly any other security software? If so, did you have any other security programs/suites on there before doing so, other than those that come with Vista (i.e. Windows Defender, Windows Firewall)?
Try this:
1) Click Start and type
c:\users into the Search box and press
Enter.
2) Double-click on your profile's folder (i.e. the one that may have your name or whatever you named the profile that you are using).
3) Right-click on the
Desktop folder, click
Properties and then choose the
Location tab.
4) Click the
Restore Default button and then click
OK.
5) Close all windows and restart the computer.
6) See if you can access
Computer but don't panic if it doesn't work and you get the same error message as there are more things to try.

7) Post back here with the results.
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