GetDiskFreeSpaceEx not working on windows XP

I've been trying to calculate the amount of diskspace on a dvd drive compared to the amount of diskspace available on a drive other than the DVD drive (local hard disk).

This function works on windows 2000, but not on Windows XP. Does anybody have any suggestions?

Thank you.

At the very least you could say how it didn't work.....but you might as well post some code too.

gg