So here is to the InstallShield Wizard. For most people, it was an annoyance. For Resident Evil 4 players in 2007, it was the final boss. And the "patched" version was the rocket launcher you bought just to skip the fight.
If you have a legitimate physical disc (or an ISO backup) and are encountering the CD key error, follow this modern solution. resident evil 4 cd key installshield wizard patched