My TP-Link router has limited access and I don’t know the exact reason behind this. After logging into TP-Link router settings, I checked that DHCP is enabled still I don’t understand why my TP-link disconnecting from internet and stopped working. Is my TP-Link router has gone faulty or it is a settings error?
If you see a red message "WAN Port is unplugged" on the status page of the Tp-Link router that means the modem is NOT plugged into the WAN port of the router properly. Please plug it in and make sure the red message will be gone.
Some ISP will register the MAC address of your computer when you access the Internet for the first time through their cable modem if you add a router into your network to share your Internet connection the ISP will not accept it as the MAC address is changed so we need to clone your computer's MAC address to the Tp-Link router.
Most TP-LINK routers use 192.168.1.1/192.168.0.1 as their default LAN IP address it may be conflicting with the IP range of your existent ADSL modem/router. If so the Tp-Link router is not able to communicate with your modem and cause you can't access the Internet.
Click Network-> LAN in the left side menu then change the IP Address to another one (for example 192.168.2.1) then click "Save".
Note: after you changed the LAN IP address next time you need to use the new IP address to access the router's management page and renew a IP address for your computer.
Solution 4: Power Cycle Modem and Tp-Link Router.
TP-LINK routers can Plug&Play with most modems but sometimes we need to do a "Power Cycle" to re-establish the connection:
Solution 5: Double Check the WAN Connection Type.
An example some of your devices may have an N standard wireless adapter in them and the wirless router may be set to broadcast a N signal. If you try to connect a device that has a 54g wireless adapter to the router it wont connect or may but then drop out in use or not even see the wireless broadcast by the router.
You would have to then lower the broadcast of the wireless router so all devices worked to 54g standard in the routers wireless settings. I suspect that is your problem. Some of your devices only work on a 54g speed and the router is set to N-150 or N-300.