Adding and removing PC components
This one dates back to the first horror stories about Product Activation (PA) and how users who made even modest hardware changes to their PCs would have to reactivate Windows on a regular basis. In worst-case scenarios, so the story went, users would be shut out of their PCs because Windows detected too many hardware changes.
Hogwash. Fewer than 5 percent of PC users ever open a PC case let alone perform major hardware surgery. But if you're one of those guys who regularly upgrades your PC's hardware, you'll be happy to hear that instances of forced reactivation because of hardware upgrades are less frequent under Vista than they were under XP. More to the point, this is another one of those issues that only affects a tiny, tiny percentage of Windows users.
When Windows examines changes to the system, the two most heavily weighed components are the PC's motherboard and hard drive, in that order. If you change both of these components at one time, Windows will almost certainly assume it's running in a new computer and cause you to reactivate. "It's that old question, 'When does a boat become a new boat?," Boettcher asked, rhetorically. "When every plank has been replaced, is it a new boat?" In the case of a Windows XP and Vista-based PC, there is an algorithm that examines hardware changes and, based on an internal score, determines whether a reactivation is required.
When that happens, Windows will attempt to reactivate electronically. If that fails, the user will need to call and reactivate manually. This is the same under Vista as it was under XP, though again the algorithm has been updated to be less strict.
"This is a fairly rare thing," Boettcher said. "Edge cases can be accommodated through customer support, but it's a relatively small group: People who are building their own PCs; hard core enthusiasts." Long story short, you'll have to talk to a human being and explain what happened. Just as you have had to do with XP.