Windows Server 2012 GUI went missing after removing Active Directory

command-line-interface path windows-server-2012 powershell

Is explorer simply not starting? have you tried typing explorer.exe in the command prompt window? I guess this isn't the case you wouldn't normally get a command prompt when logging in. It sounds like somehow the shell has been removed, effectively giving you a server core install, in which case try issuing the following from the command prompt. This should re-enable the shell if it has been somehow disabled.

Dism /online /enable-feature /featurename:Server-Gui-Mgmt /featurename:Server-Gui-Shell /featurename:ServerCore-FullServer

FYI, when this happened to me, I kept getting an Error 50 when using the command above. I had to add an /all to make it work. Once I did that, it worked just fine. 

Dism /online /enable-feature /all /featurename:Server-Gui-Mgmt /featurename:Server-Gui-Shell /featurename:ServerCore-FullServer

Below worked for me

Dism /online /enable-feature /featurename:Server-Gui-Mgmt /featurename:Server-Gui-Shell /featurename:ServerCore-FullServer /all

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