If your computer is running slow, it's possible that Windows needs to be updated. If the Windows update has failed, was interrupted, or no updates are showing up, try the following:
Right click the Windows Start button
Click on Control Panel
Make sure you View by: is set to Category
Click on System and Security
Click on Security and Maintenance
Click on Troubleshooting
Click on Fix Problems with Windows Update
Click Advanced
Click Run as Administratorand then click Next
Click Advanced
SelectApply Repairs Automatically
Click Next
Select Apply this fix
Let the troubleshooter look for corrupted files and clean the registry. Then check again for Windows updates.