HEXiT :
not a good idea. ieach Xinput is o.s specific. so if you put 1 in from xp on win7 you will get an error.
use the direct x installer as it wont be just that 1 file missing.
yeah u r right.
There may be more than one file missing but there is a possibility that only this file is missing.
This type of problem comes a lot.
In my case only just one file was missing uptill now.