Follow these steps to resolve this issue.
– Stop the windows update service.
From a command prompt run net stop wuauserv
– Download and install April 2015 servicing stack update for Windows 7 and Windows Server 2008 R2 (KB3020369)
– Download and install Convenience rollup update for Windows 7 SP1 and Windows Server 2008 R2 SP1 (KB3125574) .
There is no direct download link for this. Update can be downloaded from Microsoft Update Catalog
You have to use Internet Exporer as an ActiveX control must be installed.