Ultrix has posted an interesting thread about the Windows XP product activation on the message forum

Aparently, installing the TV Tuner drivers was enough to trigger WinXP into thinking it was installed on a different computer. That was really bad, considering the expansion cards were installed, just unrecognized by the OS with working drivers. So now I have to call Microsoft, explain them the situation, and get my copy of WinXP reactivated.

Update: This is a bug in Release Candidate 1. Activation is not supposed to work that way.

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