Yall may have to update your direct X instal to teh newest one to fix this. Get it here:
http://www.microsoft.com/en-us/download/…aylang=en&id=35
This download is straight from microsoft so it is safe. I do not understand how a DX file can go missing though seeing as it is part of the core of multimedia. Maybe jsut maybe something went wrong and it was mistakenly deleted from yalls computer. But the above should fix the problem for yall.
Before updating see if your DX is up to date by typing int eh search box at teh bottom of the start menu: DxDiag. It will open the direct x interface where you can see if it is up to date or not. Plus it gives a ton of other good info if you want to peruse it.
You should have direct x version 11 if your computer is up to date.