The W10 upgrade uses the valid prior license to your new W10 license. If your W8 license is suspect then you are steering towards a cliff. Stop. Fix the W8 issue first.
So I've been running Windows 8.1 on my desktop and recently have received an error telling me that my product key is being used by another machine (which to my knowledge it is not) and that I need to reactivate Windows. As expected my current key will not work. I really don't want to deal with Microsoft support, so would upgrading to Windows 10 give me a new product key and serve as a workaround? Been meaning to upgrade for a while anyways.

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