Make sure your computer date & Time is correct. Mostly this problem occurs due to wrong date & Time. Here is the complete detail from Microsoft about this issue: http://windows.microsoft.com/en-us/windows/windows-update-error-80072f8f#1TC=windows-7.
If this doesn’t work for you then let us know your operating system version with “system type” 32bit or 64bit? and the screenshot of the error message.