Sony PCG-V505DC2K - Manual (Page 80)

Frequently asked questions
Why is the drive unable to write data to a floppy disk?
Make sure the floppy disk is properly inserted in the drive. See Inserting and removing floppy disks for instructions on how
to insert the disk properly.
If the disk is inserted properly and you are still unable to write data to it, the disk may be write-protected. You can either
use a floppy disk that is not write-protected or disable the write-protect feature.
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