Hi  @Thisiswhyih8net,

If you cannot configure the TP-Link range extender successfully, please refer to the situations below to troubleshoot.

Case 1: The extender's default Wi-Fi network (TP-Link_Extender_XXXX) doesn't appear.

a. Press the RESET button (hole) with a pin for 1 second (all lights on the extender would flash) to return the extender to factory default.

b. Put your device next to the extender.

Case 2. The 2.4GHz/5GHz light on the extender is still off after setup. No main network connection. 

    a. 2.4G/5G light not up means the extender is not connected to the router. Connect your phone to the host router's Wi-Fi to verify it's working.

    b. Forget the router's Wi-Fi on the phone and try reconnecting to ensure the Wi-Fi password is correct.

    c. Change the router's 2.4G Wi-Fi channel to 1/6/11 and 5G to 36/40/44/48. You may refer to this link or contact router support to change: Changing Channel and Channel Width on a TP-Link Router (new logo)  

    d. Disable security settings like Mac filtering or Access Control on the host router. Please contact the router support for guidance.

Note: If there is more than one extender, ensure that their Wi-Fi names are different from the main router's so that they can connect to the router's Wi-Fi without issue. Follow this link to change the extenders' Wi-Fi name: How to change wireless settings of TP-Link range extender on Tether APP