I ran into this issue as well. I went to the download center and manually pulled the update down. When I attempted to install it, it returned a message stating that it was not applicable to my system so apparently this update is not needed even thought Windows Update thinks it is.
Make sure you are downloading the x64 if you need it. If it doesn't say x64 then you have the 32 bit and it'll say that when installing on a 64 bit system.
Dave