Hi,
These updates are usually difficult to install and can sometimes cause compatibility issues. It is still best to update Intel Corporation - Extension - 21.0.0.0 driver from your PC manufacturer's support website.
If you are not experiencing any issues, I recommend hiding the update using the Show or Hide tool instead.
Download and install the tool here: http://download.microsoft.com/download/F/2/2/F22D5FDB-59CD-4275-8C95-1BE17BF70B21/wushowhide.diagcab then run the troubleshooter. Choose to hide the Intel Corporation - Extension - 21.0.0.0 driver update so Windows will not install it again.
Click Advanced > Check the Apply repairs automatically box, and hit on Next > Hide Updates.
Note: If you encounter a warning message while downloading the file, select 'Keep.'