I'm not an MSDN (Microsoft Developer's Network) subscriber, but it sounds like you were sold a copy of Windows with an MSDN key. I believe that there's nothing unusual about your Windows copy, but the key was spotted by Microsoft as being used illegally and has been blocked. It probably worked at one time, but it is now useless.
You dealt with a crook who may have thought that he was ripping off Microsoft. Instead, he robbed you.
I suggest that you report it to Microsoft. They may be able to help you obtain a legitimate license at a lower cost than for the full retail product. https://www.microsoft.com/en-us/howt...fr/Report.aspx
(I've never used this page, personally. You have the option of reporting a counterfeit anonymously, but that may not help reolve your problem.)