You probably won't feel the need to do that quite so often with XP. I do mine only once a year at the very most, and even then, that's being picky! Mind you, it depends how much junk you find yourself ending up with over time.
Obviously, any hardware changes may mean you need to re-register.
So, if your HDD dies, and you use Acronis to put the image on another HDD, you may have to reactivate.
The "activation count" that watches over hardware changes can be triggered between taking an image, and restoring it, particularly as the image may have been taken months earlier, and you may have made several adjustments to the hardware in the meantime. It seems as it it's not counting in "real time", and the image isn't aware that months have passed between the updates.
Sorry, I know what I mean, but that reads so unclearly. Have just got better from 'flu!!
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