Any RDP session, from a mac or a windows PC, causes the ports to go missing. I remote control my DAW from my studio for tracking from in the room. Guessing I am not the only one using that as part of their workflow.
Running Windows 10 latest build, and Cubase Pro 9.0.1
By default Remote Desktop connection has a setting of “remote audio Playback” set to Play On This Computer.
If I change that to “Play On Remote Computer” the midi ports appear as normal. If not, they show as “missing”
Click on Local Resources
Click Settings on the Remote Audio section
Choose the radio button for “play on remote computer”