It's been debated what happens when Microsoft goes under and takes the activation servers with them. That's an unlikely scenario. What has happened is that someone (bad) uses your product key and you didn't know.
That's one of the reasons 10 doesn't use such keys but activates and well, that's all on the web so why duplicate that here.
When you get back from your time travel from 2020, we'd like to know.
I want to buy few licenses of windows 7 from market before they go out of stock for future use. It will help in case any existing or new computer requires windows 7. I have one doubt related to this issue.
1) Is there any expiry date on windows 7 oem/retail cd for installation or activation before due date? Is it possible to install windows 7 cd purchased today in 2020?
Thank you.

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