Hi Muniman2,
Do you recall making any changes to the computer prior to this issue?
The Issue could be caused by some third party softwares or security software present on the computer, I would suggest you to try the following steps to narrow down the issue:
Step 1: Disable the security software; follow the steps mentioned in the link below
Disable-antivirus-software
http://windows.microsoft.com/en-US/windows7/Disable-antivirus-software
Important: Enable the security software back once everything is done.
You may temporarily disconnect the computer from the internet during this test.
Step 2: Put the computer in clean boot and test
Follow Step 1 in the link below,
How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7
http://support.microsoft.com/kb/929135
If everything works fine after a clean boot, you can infer that some third party services are causing the problem.
Proceed with the remaining steps to pin-point out the third party service.
After you figure out the problem causing program, you may have to update or install a higher version of the program, if you seldom use that software you can consider uninstalling it.
Important: - Remember to put the computer back to normal startup
follow step 7 in the link.
Thanks and Regards:
Ajay K
Microsoft Answers Support Engineer
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