I have a server with interface. I have configure all features in a server, and I want to turn it in a core server. Thereby, the server consumes fewers resources.
There are two modes to remove GUI in a windows 2012 server.
1. Go to Add or Remove Features and remove
2. Open a PowerShell and write
Remove-WindowsFeature Server-GUI-Shell and later
If you have a core server and you want to add a graphical Interface you need to open a PowerShell and write
Add-WindowsFeature Server-GUI-Shell and later
Restart-Computer to aply the changes
You need to know that Windows Server 2012 have 3 differents states:
GUI with Management Tools