HD will not boot – VFAT error

I took a HD running W98se from a P60 that was working OK and put it into a P66 that had been running W3.11. Problem is I cannot get it to load windows – I always get this error;
VFAT Device Initialization Failed – a device or resource required by VFAT is not present or is unavailable. VFAT cannot continue loading. System halted.
The drive boots OK when replaced in its original PC, so I’m guessing the P66 BIOS does not recognize the formatting on the HD??? I’m no expert, so anyone help me with a work-around please?