Where can I find .WAV files my computer will play?

FYI, I have MusicMatch Jukebox installed on my computer(it came that way). I am desperately seeking .wav files it will play, so I can customize the sounds (window shut down, error, etc) on my computer but it seems that most of the .wav files out there it stubbornly refuses to play.
Any hints on what I can do or where I can find files that MMJ will play?

TYIA.

IDBB

What version of Windows do you have?

I fooled around with this a while ago with Windows 95, on our old computer. But I wasn’t working with a music program, just with the Windows “change your sound here” menu’s built-in acceptance of whatever .wav file I typed in the box.

IIRC, I found some cool sounds on Compton’s Encyclopedia and KidPix Deluxe on CD-ROMs. I opened up Explore (right-click on Start) and looked at all the file names that were on there in Drive D (my CD drive) when the program was loaded, and looked for .wav files.

IIRC I had to save it onto a floppy and then tell the “Change your sound” menu to go look in Drive A for filename whatever.

You can also Google “.wav” and mess around with whatever turns up. Is that what you’ve been doing?