Tp Link extender is not connecting and showing red light

plug in the extender into the wall socket at least 5-10 feet away from the router for the initial setup.
press and hold the WPS button on the router for 10 seconds and then on the extender for 5 seconds.
now wait till the WIFI lights are solid and then you can use the same wifi password as of your router for extender also.
You can follow these steps to setup your Linksys Range Extender:-
>Place the Linksys range extender nearby to your home router and power it on for the initial setup.
*Reset the extender by pressing reset button for at least 20 seconds and then wait for the light to get stable.
>Press the WPS button on your extender and hold it down for 3-5 seconds.
>Within the 1-minute press WPS button on your home router.
>Wait for the extender lights get stable and now try to connect any of your wireless devices with the extended network.
*If you want to connect your range extender with 5GHz network then repeat the same steps once again.
For new TP Link Extender.
Just press the WPS on your router/modem first for 1-2 seconds, then press the WPS on TP Link Extender for 3-5 seconds.
Now wait for 2 minutes.
The difference in light color and pattern will confirm its connection.
For Used/ old TP Link Extender: If its an used TP Link Extender then first reset it using a paper clip to press the reset button in a tiny hole for 30 seconds.
Now its brand new, or by default one.
Wait for 2 minutes after reset then proceed further as setup New TP Link Extender.
Its now extending your home network with same password as of your home wifi.
Note:
1. During setup, make sure that the TP Link Extender is placed within 7-10 feet from Router, at the time of setup, or in the same room.
2. Two minutes patience is the Critical Time that make the difference between success and failure in Setup.
3. Best of luck
If you are getting a red light on the Tplink Extender, it could be because of several reasons.
> The distance between the router and extender is too far and they are not able to communicate
> The firmware of the Tplinke extender is corrupted which means you can throw this extender and get a new one.
> The setup did not go through successfully – reset the extender and re-setup it again.