The cleverest floppy disc protection ever? Western Security Ltd

My father bought a 386 for his work to replace a 286 which only had a 5.25 floppy drive. The 386 had both a 3.5 and 5.25 floppy drive so he quickly switched to the more sturdy 3.5 disks and moved a lot of work to the 3.5's.

Everything was working great until he got a second similarly spec'd 386. For some reason the machines couldn't read each others 3.5" disks. So he called his programmer friend who stopped by and did some testing. Both machines could format/read/write their respective disks no problem. So he formats and writes a test file to a disk from each machine and takes them home with him.

My father gets a call from him the next day: "call the vendor and have them give you a new 3.5 drive in the original machine" Turns out the heads in the original machines 3.5 drive were slightly misaligned mechanically to the tracks. This caused the disk to be perfectly workable in the bad drive but fail to read in any other machine.

Since when would anyone remember how to properly write something, when the representation he has is the phonetics in his head?

Nobody thinks "It's disk, because it comes from diskette."

Why do people argue as if anyone would think like that? - Though I don't doubt that it's the origin. Are we supposed to know the origin of (every)thing(s)? - We mostly don't.

To then write it "disc" makes sense, except you are from Germany.

To then pseudo-intellectually pretend that people know whatever and what not and don't rather go by guts feel (what it sounds like) is blatantly dishonest.

Nope, you did not miss anything. Many of these old DOS game floppy protections could be bypassed by a single byte change to the exe (or com, depending on the game) file. The time consuming part was working out exactly which byte to change.

Source: I cracked most of my DOS games back in the day, using nothing more than DOS's supplied 'debug' tool, so I did not have to go find, and insert, the floppy in order to play the game. On many of them, changing a single JC to JNC or a single JE to JZ (or the reverse) was all it took to bypass the copy protection. A few others took a few more bytes worth of patching, one had to convert a conditional into an unconditional branch or otherwise nop out a small code segment. The one that required the most effort was MicroProse's Apache helicopter simulator. They used the "weak sector trick" but the contents of the "weak sector" was also a small bit of the overall game code. So for that one I created a loader that hooked the disk interrupt and when it detected the weak sector read, it returned the sector data and the proper "disk read error" state for the rest of the game to work with.

uh ? that's pretty much how I think all the time when writing words for which I'm not sure of the spelling