I've got a machine on my home network running Windows Server 2012 (Based on Win8). The problem is, my taskbar disappears completely.
When I minimize an application rather than minimize to the taskbar it simply closes the window as small as it can as if the taskbar never existed (see photos at bottom).
The problem first presented itself after I accessed the computer from outside my local network I'm using a Linksys router and mapping to the server IP, port 3389.
After a restart the problem goes away, I will update when I have more information on how frequently or what may trigger.