expanding on T-R-A's comments, PARK was a small dos program which was run immediately before powering off. There were various versions of this with similar names, which were supplied by the pc makers, not Microsoft. After powering on, the hdd would run normally. I believe in more modern hdd's head parking is inbuilt.
if the IBM has not been used for some time, the cmos (or whatever) battery may have failed.
When this happens the bios can return to default settings. This would reset date, time, hdd parameters etc. The pc cannot then access the hdd.
If this has happened, leaving the pc powered on for a couple of hours may recharge the battery. If not it will have to be replaced.
You should check the hdd params and if incorrect for your hdd, re-input.
Please advise back on progress.
Good Luck - Keep us posted.