I got this on the MS website mate, dont know if it helps?
I installed a missing codec, but I still can't play the file. Why?
Codecs can be written for 32-bit or 64-bit operating systems. If you are running a 64-bit version of Windows, you need to install 64-bit codecs. If you install a 32-bit codec on a 64-bit operating system, for example, the Player might not be able to play any files that require that codec.
Note that many older codecs are only available in 32-bit versions. If the codec provider does not specify whether its codec is 32-bit or 64-bit, the codec is likely 32-bit. For more information, contact the codec provider.
cheers bullet
bullet1968
"A Darkness at Sethanon", a book I aspire to model some of the charcters and scenes