It has nothing to do with the FATs on either PC; those are specific to the HDD. Does this happen with all floppies created on the same machine and then used on multiple other PCs...or is it just one floppy created on one PC and then trying to be accessed on one other PC? If it's always the same PC where the floppies are created, and you have problems reading any of them on any other PC, then I'd say there's something wrong with the floppy drive they were made on...OR...you may have run into a bad box of floppies. If it's always the same PC where you're trying to read the floppies, then I'd guess there's something wrong with the floppy drive in that PC. One more thing...can you read the floppies on the same machine they were created on?