If you receive a "Bad Serial Number given in Setup" error when launching the game, use this quick verification checklist:
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Right-click the game executable and select Run as Administrator to force the game to read the registry key. If you receive a "Bad Serial Number given
Run your Steam client or the game launcher as an Administrator . To do this, right-click the Steam shortcut, select Properties , go to the Compatibility tab, and check Run this program as an administrator . Then, verify the game files to rewrite the registry key. Multiplayer "Key in Use" or "Global Ban" right-click the Steam shortcut