"Code 10" on Primary IDE Controller

I have a customer who brought in an old compaq armada E500 laptop w/ windows 98se; He had tried to install drivers for a usb memory stick, at which point he said his cd-rom drive was no longer present in 'my computer'. Sure enough, in device mgr. the primary ide controller has the yellow excl. mark next to it, and "code 10" in the properties of the device. In safe mode, both primary and secondary controllers show up as fine. I can't find any evidence of usb stick software, I've tried removing all the devices in safe mode to try to have them re-found (even found usb drive references in device mgr in safe mode, and removed those too), and scoured google for answers. It's a business laptop so formatting is apparently not an option.
I looked in the registry and found no "noide" registry entry to delete (as mentioned by several articles found on google) and no "upper or lower limits" keys to delete, either.
Anyone have any ideas?