Method 1: Perform clean boot on the computer
You need to perform a clean boot to identify the faulty or conflicting program on your computer.
Clean Boot Troubleshooting.
1. Click Start, type msconfig in the Start Search box, and then press ENTER.
If you are prompted for an administrator password or for a confirmation, type the
password, Or click Continue.
2. On the General tab, click Selective Startup.
3. Under Selective Startup, click to clear the Load Startup items check box.
4. Click the Services tab, click to select the Hide All Microsoft Services check box, and then click Disable All.
5. Click OK.
6. When you are prompted, click Restart.
7. After the computer starts, check whether the problem is resolved.
If the issue is resolved check which third party program is causing the problem, referring the link given below:
http://support.microsoft.com/kb/929135
Reset the computer to start as usual.
After you have finished troubleshooting, follow these steps to reset the computer to start as usual:
1. Click Start, type msconfig.exe in the Start Search box, and then press ENTER.
If you are prompted for an administrator password or for confirmation, type your password, or click Continue.
2. On the General tab, click the Normal Startup option, and then click OK.
Method 2: Reset windows update component
Try to reset windows update and check if issue persists.
To reset the Windows Update components automatically, click the Fix it button or link. Click Run in the File
Download dialog box, and then follow the steps in the Fix it wizard.
Check out the Microsoft article given below
How do I reset Windows Update components?
http://support.microsoft.com/kb/971058
Note: we will try to install the updates one by one and check for the issue.
Download and install the Windows Update agent.
The Windows Update Agent lets you manage which updates will be installed on your computer. The Windows Update Agent
works together with the Windows Update Web site to provide the latest updates to your computer. The Windows Update Agent also works together with servers that are running Microsoft System Management Server and Windows Server Update Services (WSUS) in a corporate environment.
For more information about how to download and install the latest Windows Update agent, click the following article number to view the article in the Microsoft Knowledge Base:
How to obtain the latest version of the Windows Update Agent to help manage updates on a computer
http://support.microsoft.com/kb/949104/
http://windows7.iyogi.com/upgrades/windows-7-update-problem/