I've got exactly the same issue as above and have also just bought a new unused and sealed copy of Halo 2 PC for Vista from Amazon and after installing and trying to run the game I'm also getting a message that the Product Key is invalid - frustrating!
I know the game is old now but if the game is a genuine sealed newly purchased item then there's no excuse for the product key not working and I know loads of people have been having the same issue recently when re-visiting the Halo games back catalogue because release of Halo 4 has re-awakened interest in the series. Would be great if someone out there can help resolve this one. Harassment is any behavior intended to disturb or upset a person or group of people. Threats include any threat of suicide, violence, or harm to another. Any content of an adult theme or inappropriate to a community web site. Any image, link, or discussion of nudity. Any behavior that is insulting, rude, vulgar, desecrating, or showing disrespect.
- Any behavior that appears to violate End user license agreements, including providing product keys or links to pirated software.
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