Took a while to find this
On windows 7
C:\Users\yourUserName\AppData\Local\Microsoft Corporation\Remote Desktop Connection Manager\RDCMan.settings
- If you want to group your VMs, create a RDCMan file, add a group, then Add servers to groups, don’t add servers lose to a file, or drag and drop gets screwed up.
- If you have a server lose in a file you will not be able to create a group in that file in the UI or via drag drop.
Probably by design 🙂