dude... 5.3.2600.2180 is the version and build of your windows. 4.9.0.901 is the version and build of the directx. I suggest you to get the 60 MB dx redistributable from microsoft.com and use it.
And you cant replace files because of SFC or System File Checker. it detects any modifications of system files, and when it does, it automatically restores a safe backup.for bypassing it, use safe mode
