OS not found..?

Open the tower and make sure all the connectors are set properly...

While you're in there, check the CPU cooling fins to see they aren't full of dust...

If I got that message in W98se, I'd do the above.. then I'd start fresh, by pulling the battery for half an hour, then disconnect the tower from the Net, and do a complete fdisk new-partition install from CD's, including all the updaters, put on to CD from safe sites like majorgeeks... Add Sunbelt-free from a CD, set to ask on everything, before connecting to the Net... When I was running W98se, that worked well for me... I just forgot about microsoft websites... And I block IE and OE, and use SeaMonkey...

The big thing I found with W98, is that you need to use old softwares, like the ones from "OlderVersions"... The newer softwares only messes up W98.. especially macromedia and shockwave, which causes all those W98 lockups... Macromedia software is way too powerful for W98...

Run scandisk for bad clusters... Get hd's at garage sales...