How old is your floppy drive ? If it is more than 4,5 years it may be dirt that is corrupting your disks. A floppy drive has little to no protection against dirt and dust.
Could also be your disks .... are they new diskettes ? If they too are quite old then it could be the problem. Floppy disks were known to lose data easily. Even the smallest magnetic field, like a tv set, can wipe the data off of those disks.
If you provide more info it would be easier to pinpoint the problem.
The most common cause I've seen for losing data on a floppy is dust. Most such drives are in a case with more air exhausted by fans that supplied. So the case sucks in air through the available openings, and an easy one is the front slot of a floppy drive. This ends up depositing dust inside the drive, often accumulating on the heads. When you insert a disk and it turns, sometimes the dust balls scrape a groove in the disk surface and there goes a track!
Because my use of the floppy was infrequent, I got into the habit of using a floppy drive cleaner (alcohol solvent) before putting in the disk. Then I'd stick a thin thing into the front slot to keep the spring-loaded slot cover open and hasten the air flow to dry out the alcohol in a few minutes, and THEN use the disk.
Only problem this gave me is, where do you find a cleaner kit? These drives have become so unpopular that few parts shops carry the cleaners. The last one I bought, after phoning about ten shops, was their last one, and I got the feeling they were glad to be rid of that old inventory!
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