Invalid Function message on CD & A drives

[usagi]

A WIN 2000 now 'throws' an Invalid function whenever I try to acces the A:\; D:\ or E:\ drives.
No conflicts show i device manager. I have replaced the data ribbons. When the system boots up as the desktop appears, an 'invalid function' message will pop up.
I can cancel that and then access the C:\ drive AND network shares. But get that error message trying to to the A drive or either CD or CDR drives.

Any help would be appreciated. All current MS updates are installed; Norton's Corporate 9.0 is current and shows no infection; and have current newest drivers installed.
HELP!

[degsy]

Welcome :)

Do the drives show in the BIOS / POST screen?
How about DOS or Safemode?

[usagi]

Do the drives show in the BIOS / POST screen?>>> did not check the BIOS screen ..oops.



How about DOS >>>No...when I try to change to A:\ error message device not ready



or Safemode?>>> they 'show' but can not access

[degsy]

If the drives cannot be accessed in DOS or Safemode then it would suggest a Hardware error.