Error Installing Update KB2917929

I'm running Windows 8.1 Pro x64 and i wanted to update my Sony Xperia M system via Sony PC Companion while my mobile is connected to PC with USB cable. When i clicked on "update" on my PC companion it gave me an error. It said that I need to download update for windows KB2917929. I went on Microsoft forums and downloaded update for my Windows x64. When I tried to install it it gave me an error again. "The update is not applicable to your computer". What should I do? Thank you.

I'll try following the instructions of this post in the weekend, hope this helps:

xda-developers - View Single Post - [Drivers] FlashTool Xperia Driver Pack (v1.5) [20140318]