accessible

Mi computer no reconoce el flopy disk, not my CD-ron,
recibo el siguiente mensage "A:\ is not accessible,
incorrect funtion"

I get the mesager A:\ or E:\ "is not
accessible" "Incorrect function"when i
try to run the folppy disk or my CD rom.
I uninstalled twenty times the A, E, D, F drives, when
restarts windows it reinstall it all again, but still not
working, I uninstalled in safe mode, and not luck either.

BUT I try in safe mode and all work perfect!!!!, but not
in normal windows!!!!!!!!.

I got windows 2000, what is Rollback Driver? I cannot find
it.
Please any suggestions.