RDP known as Remote Desktop Protocol which is developed by MICROSOFT.
This service is provide to connect another computer over a network connection.
The RDP service by default listen TCP port “3389”

Follow the steps to change the RDP port:
Steps:
1. Go to “RUN”

2. Type “regedit” —>>to enter into registry

3. Click on the follwing registry subkey:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\TerminalServer\WinStations\RDP-Tcp\PortNumber

4. click on “Modify” and then click on “Decimal”

5. Type the new port number and save it.

6. Quit the registry

7. Restart all RDP services or restart the computer

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