Hi bobo6335,
· Do
you remember making any changes to the computer after which the issue started?
Try the steps mentioned below and check if it helps:
Step 1:
Place the computer in a clean boot state and troubleshoot the issue and check if it helps. You can start Windows Vista or Windows 7 by using a minimal
set of drivers and startup programs. This kind of startup is known as a "clean boot." A clean boot helps eliminate software conflicts.
**How to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7**(Step 1: Perform a clean boot)
If your issue is resolved after performing Clean Boot, then follow the steps mentioned in the following KB article to narrow down the exact source: **http://support.microsoft.com/kb/929135**
Also, see the section on how return your computer to a Normal startup mode by following the steps under “Reset the computer to start as usual”, after
performing the clean boot troubleshooting.
Step 2:
Run System File Checker tool to troubleshoot missing or corrupted system files on Windows Vista or on Windows 7 and check if it helps.
How to use the System File Checker tool to troubleshoot missing or corrupted system files on Windows Vista or on Windows 7
Hope this helps.
Thanks and Regards, Santosh Y – Microsoft Support
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