Router Not Connecting to the Modem: How to Fix “WAN Port Unplugged” and No Internet

The modem’s lights look fine, a computer plugged straight into the modem gets online — but nothing works through the router. Or the router’s status page says “WAN port is unplugged” even though there is clearly a cable. This happens often right after installing a new router, and the cause is almost always one of a handful of things. Work through the steps below in order; they follow the troubleshooting path TP-Link recommends for exactly this situation, and apply to any brand.

Signs the Router Is Not Getting Internet

• The router’s Internet or WAN light is off, amber or red; see router lights meaning.
• The router’s status page shows “WAN port is unplugged”, “Cable disconnected” or “No internet”.
• Devices connect to the router’s Wi-Fi but have no internet.

If the modem itself shows no connection — its online light is off or blinking — the problem is between the modem and your provider, not the router. See the last section, “When to Call the Provider”.

Step 1: Read the Router’s Internet Address

Sign in to the router — what is my router IP helps if you do not know its address — and open the status page. Look at the Internet or WAN IP address. TP-Link’s guide calls this the key starting point, because it tells you whether the problem is the connection to the modem or something further on:

0.0.0.0 or empty: the router got no address from the modem. Continue with steps 2–5.

A private address (192.168.x.x, 10.x.x.x) from the modem: the router is connected, but your modem is a gateway that also routes. That works, but creates double NAT; if devices still have no internet, go to step 5.

A valid public address, but still no internet: the router is online. Try setting DNS servers manually in the router (for example 8.8.8.8 and 8.8.4.4, as TP-Link suggests) — see DNS server not responding — and restart the router.

Step 2: Check the Cable and the Port

The cable must go into the WAN port. On the router, it is labelled Internet or WAN and often has a different color. A cable in one of the LAN ports looks connected but gives no internet. On the modem, use its Ethernet port (on a gateway, a LAN port).

Seat both ends firmly until the clip clicks. Look at the small lights next to the ports: no light on either end means no link.

Try another cable. A damaged cable is a common cause of “WAN port is unplugged” when the plug is clearly in. Our guide on Ethernet cables not working explains how to tell.

Try the cable between the modem and a computer. If it works there, the cable and the modem port are fine, and the router’s WAN port is the suspect. A WAN port that never lights up with any cable may be faulty.

Step 3: Test the Modem on Its Own

Disconnect the router and connect a computer directly to the modem with a cable. Restart the modem first, wait until its lights settle, and then check for internet on the computer.

No internet on the computer either: the modem or the provider is the problem. Restart the modem once more; if it still fails, contact the provider.

Internet works on the computer: the modem is fine, and the issue is between the modem and the router. Continue.

Step 4: Restart Both in Order

Some cable modems hand out their connection only to the first device they see after starting. If you swap a computer for a router — or an old router for a new one — without restarting the modem, the modem may keep waiting for the old device. A restart of both, with a pause, clears this.

Turn off the modem and the router and leave them off for about a minute. Then start them one after the other, waiting until each has fully started. Most guides start the modem first and then the router; TP-Link’s troubleshooting guide for this exact problem turns the router on first and the modem second. If one order does not work, try the other. Our guide on rebooting a router has the details.

Step 5: Check the Router’s Internet Settings

Connection type. The router must use the same connection type as your provider: Dynamic IP (DHCP) for most cable and fiber connections, PPPoE with a username and password for DSL and some fiber, or Static IP. A router set to the wrong type will not connect. Find the setting under Internet or WAN, and ask the provider if you are not sure. A few fiber providers also require a VLAN ID.

MAC address clone. TP-Link notes that some providers tie the internet connection to one specific device’s MAC address. If a computer works directly on the modem but the router does not, use the router’s MAC Clone option while connected to the router with a cable from that computer — the router then presents the computer’s MAC address to the modem. Then restart the modem. Calling the provider to register the router’s MAC address solves the same problem.

An address conflict with the modem. If the modem is a gateway that uses the same local address range as your router — both at 192.168.0.1, for example — the router cannot route between them. TP-Link’s fix is to change the router’s LAN address to a different range, such as 192.168.2.1, in the LAN settings. You then reach the router at the new address.

Provider gateway in front? If your “modem” is a gateway, consider bridge mode so that only your router does the routing; see modem vs router vs gateway.

When to Call the Provider

Call the provider when the modem itself has no connection, when a computer plugged straight into the modem does not get online, or when the connection type, PPPoE login or MAC registration is unclear. Have the modem’s model, the router’s WAN status and the steps you already tried at hand. If none of the steps help and the router is new, a factory reset and a fresh setup — see how to set up a new router — rules out a wrong setting left over from earlier attempts.