In order to connect to a user’s laptop via RDP, the technician should open port 3389 on the Windows firewall. This is because RDP uses port 3389 for communication12. The other options are not necessary or relevant for establishing an RDP connection.

Confirming the user can ping the default gateway is not required for RDP, as it only tests the network connectivity between the user’s laptop and the router. RDP works over the internet, so the technician should be able to ping the user’s laptop directly using its IP address3.

Changing the IP address on the user’s laptop is not needed for RDP, as long as the IP address is valid and not conflicting with another device on the network. The user’s laptop has a valid IP address of 192.168.0.45, which belongs to the same subnet as the gateway (192.168.0.1) and the subnet mask (255.255.255.0)4.

Changing the subnet mask on the user’s laptop is not required for RDP, as long as the subnet mask matches the network configuration. The user’s laptop has a correct subnet mask of 255.255.255.0, which defines a network with 254 possible hosts4.