Ports - Custom Services Apply Cancel Service Name Protocol TCP/UDP TCP UDP External Port Range (1~65534) (Specify ports and/or port ranges spilit by commas, example: 30, 50-60, 65500-65510) Use the same port range for Internal port Internal Port Range (1~65534) (Specify ports and/or port ranges spilit by commas, example: 30, 50-60, 65500-65510) Internal IP address Check "Use same port range for internal port" Internal starting port (Leave Blank) Internal ending port (leave blank) Internal IP address (Enter the IP address of the raspberry pi) Click on "Apply" I can not leave it Blank, click Apply it will work