so I installed visual studio 2019 in Windows 10 partition, but I use Visual Studio whilst in Windows Server 2019 while the program itself is on the windows 10 partition. Get It?
Did you run the VS install routine also from Server 2019 instance? Could be a problem if you didn't. As to licensing you can read on here.
https://visualstudio.microsoft.com/wp-content/uploads/2020/09/Visual-Studio-Licensing-Whitepaper-Aug-2020.pdf
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