You could choose one of the following methods.
Method 1. Use Open Ports Setup to redirect incoming traffic on ports 1503 (TCP) and 1720 (TCP) to the desired PC:
Method 2. Enable DMZ Host Setup:
You could choose one of the following methods.
Method 1. Use Open Ports Setup to redirect incoming traffic on ports 1503 (TCP) and 1720 (TCP) to the desired PC:
Method 2. Enable DMZ Host Setup: