Hi,
Is the computer in domain environment?
1. Please disable your network card and reboot the computer to check the result.
2. Disable the third party startup items and services by performing the clean boot.
How to clean boot:
http://support.microsoft.com/kb/929135
Please monitor the system in the Clean Boot environment. If the problem does not occur, it indicates that the problem is related to one application or service we have disabled. You may use
the MSCONFIG tool again to re-enable the disabled item one by one to find out the culprit.
3. Check if system restore can help to resolve the issue.
a. Click Start. In the search box, type System Restore, and then, in the list of results, click System Restore.
b.
On the window that appears, click Next and select the date and time on which the computer booted normally and click Next.
c. Wait for the process to complete.
Tracy Cai
TechNet Community Support
