Restore the RDP file association with mstsc.exe

If you have elected to do so during the installation, the *.rdp file extension has been associated with Remote Desktop Manager, this means that it does not use the mstsc.exe client from Microsoft anymore.

Solution

From an elevated command prompt (run as administrator), run the following command: ftype RDP.File="%systemroot%\system32\mstsc.exe" "%1" . Add this command to the domain logon script to fix the issue for all users at once.