WIN98SE sound problems

I’m getting an error when trying to set up system sounds with Win98SE. When double clicking a .wav file in explorer or testing a sound in Control Panel/Sounds I get the error that the .wav file is damaged or in use by another program. The .wav filescan be played in MP7 with no problems(so it’s not the sound card) but they will not play for any system events they are associated with. I uninstalled & re-installed Win media support with no luck.