DirectX Problems

I've recently installed Windows XP Professional and I downloaded the automatic updates. These however mucked up the computer and left a message saying error with winlogon or something when i booted up. I repaired the system and everything appeared fine except DirectX and Windows Media Player. I fixed Windows Media Player by uninstalling it and reinstalling it. However none of my programs can recognise DirectX. I am running 9.0c so it should work but nothing happens. So i tried going to Start > Run > dxdiag and when it starts up it says 'Error, could not get basic sound info., result code = 0x80070057 (invalid argument(s))'. So I click OK and everything else works, except for when I go to DirectX Files and it says several files are old versions. I have reinstalled it several times but nothing works.

Can anyone help?

Thanks

Rob

EDIT: The 'Error, could not get basic sound info' problem doesnt occur now i have installed SP2 but the others do.

 

Please can someone help I'm having real problems?

 

Thanks but I've looked there and nothing solves the problem.