For StarCraft, the installer would do some math on all but the last number, then see if the result of that matched the last number to decide if the key was valid. So you could enter random numbers, then just retry while changing the last digit and guess a valid key in max 10 tries
GXYPJ-4W67Q-6273F-QJ7FR-9MW4M
Is this an illegal number?
only illegal if Microsoft still supported XP.
(for some reason all 3s worked)
For StarCraft, the installer would do some math on all but the last number, then see if the result of that matched the last number to decide if the key was valid. So you could enter random numbers, then just retry while changing the last digit and guess a valid key in max 10 tries
Or 11 - the last digit could be X (for ten) if they were using the modulo 11 check digit system.
Same for Counter-Strike 1.6, but there it was
XCNF8-R99R9-R4XV8-2VQD7-FJP6M
This is how Elrond felt when someone spoke the words from the one ring.
Wasn’t that FCKGW-RHQQ2-YX… Something 🤣 knew that entire key for a pretty long time, but looks like it starts to fade.