Hi I am running a testing lab AD in my home lab serving for testing, I had just download the ISO, is that possible for me to upgrade the Windows from 2016 DC GUI to Insider build with GUI (existing I have application and ADDS up and running)
Generally speaking, it is possible to upgrade from one edition to another edition that is the same or closely related. Server Core should be upgradable to Server Core, Server with Desktop Experience should be upgradable to Server with Desktop Experience.
In this specific case, we are not releasing the Server with Desktop Experience editions to the Insider community, so unfortunately there is no version of Server with Desktop Experience to upgrade to. If you had a Windows Server, version 1709 Server Core version, then you could upgrade it to the latest insiders build, which I believe is build 17079.
Please let me know if you have any follow-up questions.
Best Response confirmed by
Calvin Wong (New Contributor)