This in-depth look at this copy protection system by [GloriousCow ... PC Option Board that would man-in-the-middle between the floppy disk drive and the CPU, intercepting data and render those ...

Software Write Protection. Hardware writes protection is mostly available in the card reader or floppy disks. In hardware write protection there will be a mechanical switch at the side of the card ...

A DOS error message that means the floppy disk has been protected and data cannot be recorded on it. Either unprotect it or use another disk. See file protection ...

Additionally, the CRC was also altered to add another layer of protection ... with a standard IBM PC floppy disk controller; you need specialized hardware that can write different-sized sectors ...

A small, square cutout on the side of a 5.25" floppy disk used to prevent it from being written and erased. To enable the protection, the notch is covered with self-sticking tape. See file protection.