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Copy protection

Part of the copy-protection routine for the PC port of Agent USA relied on a clever attempt to socially-engineer crackers: The program attempted to see if sector 0 was writable, and if so, proceeded to write junk all over it, rendering the diskette unbootable. Why is this clever? Because the original factory diskette was write-protected (in fact, it lacked a notch completely) and the check would always fail on a factory original.


  • Zzap!
    • May 1985 (Issue 1) - #36 'It's the Zzap! 64 Top 64!'

Contributed by Trixter (9119) on Sep 28, 2005. [revised by : FatherJack (62753) and Patrick Bregger (232690)]. -- edit trivia