Hi,
- Did you make any recent changes on your system prior to this issue?
**Method 1:**Run Fix it.
Fix the problem with Microsoft Windows Update that is not working:
http://support.microsoft.com/mats/windows_update/
Method 2: If the issue is not resolve I would suggest you to try the steps in the link mentioned below.
Unable to install updates in Windows Vista, Windows 7, Windows Server 2008 and Windows Server 2008 R2
http://support.microsoft.com/kb/2509997
Disclaimer: Important this section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully.
For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft
Knowledge Base:
322756 (**http://support.microsoft.com/kb/322756/**)How to back up and restore the registry in Windows
And also note: While performing chkdsk on the hard drive if any bad sectors are found on the hard drive when chkdsk tries to repair that sector if any data available on that might be lost.
Hope this information is helpful.