Win7/win8.1 upgrade win10 after reinstalling the system requires a key?

win7/win8.1 users can upgrade freely in the first year after the release of win10. A friend has to ask win7/win8.1 to upgrade the win10 and reinstall the system need a key? Today, I will introduce you in detail, and interested friends can take a look.

Because the system is running for a period of time, it often needs to be reinstalled for various reasons. At this time, do you still need to install win7/win8.1 and upgrade to win10 as you did during the upgrade? And if this problem occurs after one year of win10 release, do you need to pay for reinstalling the system?

Gabriel Aul, head of the Microsoft Win10 Preview Experience Program, today answered questions about users on Twitter. He said that once the user device is upgraded to Win10, it can be reloaded for free at any time. Subsequently, the user used Win8.1 as an example to ask whether the responsible person's own Win8.1 account is still valid in Win10.

In response, Gabriel Aul replied that the Win8.1 key is not needed at all. For devices that have been upgraded to Win10, reinstalling Win10 will reactivate.

Although the person in charge only used Win8.1 as an example, according to him, "for devices that have upgraded Win10, reinstalling Win10 will re-activate", this policy is for Win7. Users should apply the same.
win10 preview version activation tutorial (with win10 key)