As you probably already know, by default, Microsoft Remote Desktop listens on port 3389. This is all good, but what if you are behind a firewall and wanted to allow port forwarding to be able to access multiple computers via RDP remotely but can’t because they are all running on the same port?
Well, if you’re crafty and have a decent Linux-based router like Mikrotik that will let you create packet mangling rules to change the destination port number, you can get around this, but in environments where you have little SOHO routers like Linksys or Belkin, typically this is where changing the port number that RDP listens on comes in handy. The only problem then is remembering whatever port you changed it to because then you have to specify it anytime you connect via RDP which can be a pain if you’ve got a bad memory. There are already a thousand and one articles out there to help you change the port number, this is a quick post for future reference for myself.
To change the port number that RDP listens on, edit the following registry key, select the decimal radio button (who the hell would know the hex off the top of their head?), and change the value from “3389” to some other port.
HKLM\System\CurrentControlSet\Control\TerminalServer\WinStations\RDP-Tcp\PortNumber
After you’ve done that, you will make sure that you want to update your port number or add another rule in Windows Firewall for the new port and then reboot.