A blinking red light on your D-Link extender usually indicates poor signal strength or a failed connection to the main router. To fix this, start by moving the extender closer to your router to improve the Wi-Fi signal. Unplug and reboot both your router and extender. Reconnect the extender by following the setup process again—connect to the extender's network, access the setup page, ... https://dlinkapnet.net/how-to-fix-d-link-extender-blinking-red-light/