Yes, there is antivirus program that scans boot floppy. But even if it is
the cause of the problem this scan must end some time, must not it.
Let me add that I found out that if there is no disk in the floppy drive
Windows asks to insert it.
Yes, the scan should end eventually and the floppy disk would be available
once again for use. However, there are also "on demand" settings that could
be reactivated when the floppy disk is accessed that could interfere. My
antivirus program has several options for floppies: always when accessing a
disk, only when opening files on a disk and manual antivirus scans only. A
very aggressive antivirus program could be "in the way."
Not sure what your last sentence is referring to. If you ask Windows to
format a floppy disk and one is not in the drive, it will ask for a disk to
be inserted. This message is normal and expected. It also appears if the
disk that is in the drive is not readable - damaged to the point that it
cannot be read.
When I upgraded to WinME (many would argue if that was an upgrade or not),
I ran into the situation of floppies not being accepted. Very similar to
what some run into when installing XP. Floppies that worked recently, could
not be read or formatted. Did a bit of troubleshooting and made no headway.
Bought a new box of floppies. They worked immediately and without errors.