Windows Update error with code 800B0100

First I wanna say hello to all you guys trying to solve our problems. My problem is over a two months old. Ill keep getting that error code whenever I try to install update Security Update Microsoft.NET Framework 3.5.1 on Win7 SP1 or KB2937610. I tried almost everything I knew. Use SURT,tried a manually install update,reinitialize downloads folders,use some commands on cmd to re-register dll...