I/O Disk Missing Win 98

I/O disk missing means generally one of a few things, you ribbon connector from your hard disk to your motherboard has come loose, open that machine and unseat reseat cable ensuring they are firmly in place, IDE Controller failure i.e. The controller that your ribbon cable from the hard drive plugs into on the motherboard has failed (New motherboard required) or the unfortunate hard disk failure.

First thing to check is the cable seating, if no change and a spare drive try plugging it in and see if it's recognized, If yes then your hard drive has failed, If no then possible IDE controller failure try in in the alternate IDE slot and see if you get the same results. It is unlikely that both slots would fail, although it is possible.

If you suspect it is the controllers get a friend to try the drive in their machine and see if it's picked up.

Ultimately a new hard drive is a far cheaper solution than a new motherboard, but dependant on how valuable the data is, there are companies out there who will recover this for you at a very expensive cost to you.

Hope this helps