Remote access troubleshooting
Port forwarding not working? Start with these checks.
If the rule looks right but outside visitors still cannot reach your service, the problem may be the network path rather than the hostname or port number.
Your ISP may use CGNATIf your router does not have a usable public IPv4 address, port forwarding has nowhere public to send traffic.
You may have double NATAn ISP gateway plus your own router can create two layers that both need the right rule.
The service may not be listeningThe local app, server firewall, or wrong LAN IP can block traffic before the router rule ever matters.
The ISP may block the portSome residential connections restrict selected inbound traffic even when the router is configured correctly.
Fast troubleshooting path
- 1. Confirm the local service works. Test it from another device on the same LAN before testing from the internet.
- 2. Check the router WAN address. Compare it with the public IP shown from outside your network.
- 3. Look for double NAT. If an ISP modem/router sits in front of your own router, both layers may matter.
- 4. Verify the target LAN IP and firewall. Make sure the rule still points at the right device and the device accepts the traffic.
- 5. If direct inbound access is blocked, stop fighting the wrong battle. Use Public Tunnel for web apps or Static-IP Relay for TCP services.
What to use when the router is not the real problem
If the public IP itself is missing or the router cannot be changed, Dynamic DNS alone will not fix the path. Start with what CGNAT is, then compare Public Tunnel with port forwarding or review the broader Remote Access options.
Need a route that does not depend on port forwarding?
DNSExit Remote Access is built for the cases where the local service works but the network path will not cooperate.