In theory, WGA can distinguish between a new hard drive and a new PC. In reality, though, it sometimes gets confused and asks you to reactivate Windows--usually a painless chore. If reactivation fails, call Microsoft's Activation hotline at 888/571-2048. To speak with a human being, say "agent" when asked which option you want, and don't waver when the automated phone system attempts to convince you that you would be better off talking to a machine. The hotline is open around the clock.
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