floppy not working

I recently rebuilt my computer. I have a K7 Triton 400 Ga-7VA mobo and everything worked fine until recently I went to use the floppy. I know this floppy worked fine in my other computer… besides… I tried three different floppy drives I had here and none of them would work in this computer. The light comes on and it says please insert disk into drive A. Or something very similar to that. This is driving me crazy and I have no idea what the problem may be. I tried switching ribbon cables too and that did nothing.