I have an Inspiron 7000 with xp loaded.

Everything was good till I took a hard drive from a damaged but otherwise identical computer and put it in this computer to reinstall the OS (w98) which had become corrupted. Got everything working, then put the original hard drive back in. Now neither touchpad nor mouse work.

I switched the options for touchpad back and forth in CMOS, tried to add new hardware automatically and from list of manufacturers, reinstalled XP, tested mouse from Dell Diagnostics diskette. Finally I bought a USB mouse which works. But need to be able to use the touchpad in my work.

The weird part is that if I put the old harddrive with w98 into the computer, touchpad and mouse work. So there is nothing wrong with them or with the port. It seems XP no longer sees the port or hardware during boot.

Any ideas?