Hard reset TP-LINK TD-W8920G

Factory reset (Hard reset) Locate the reset button on the rear panel. With the router powered on, press and hold the button down for more than 5 seconds. (You can use a pin to press inside the reset button-hole). Release and wait for at least a minute for the reset process to finish. Option 2: Press the reset button of the Router, and then power on the Router, hold reset button pressed down for about five seconds. Release.
Firmware Firmware link
Default username admin
Default password admin
Default IP address