Hi there,
Are you asking for help fixing the error code you received, or are you stating that you DID FIX IT, and are attempting to share the solution with the rest of the Forum users? If it's the latter, and your Win7/8.1 was licensed, the Win10 will be Activated without problem. Win10 preview versions did require massive updating, some versions more than others. A Win7/8.1 free upgrade via the Internet is known to take less time, but it depends on lots of factors including the age of your computer.
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