Back when floppy drives cost $500, they had some semblance of quality.
Now that they're $11 at Fry's (that's $5 before markup, $1 before shipping
from Japan, and $.13 of materials) they are almost without fail ... prone
to fail.
You might try using brand-new formatted disks. Be sure if you put a
floppy into a Windows box that you write-protect it, since Windows writes
on a disk even if you only do a directory! (It's updating the "Last
Access Time." Rah.) Thus merely reading a disk on someone else's machine
with a misaligned drive can trash the disk.
\\/
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