Sony PCG-FXA59 - Manual (Page 106)

Troubleshooting Drives, PC Cards and Peripheral Devices
My floppy disk drive cannot write to a floppy disk.
 Check that the floppy disk drive is properly inserted into the multipurpose bay. See To reinsert the floppy disk drive
for more details.
 If the floppy disk is write-protected, disable the write-protect feature or use a floppy disk that is not
write-protected.
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