Hard reset TP-LINK AC1900 / Archer C9

Factory reset (Hard reset)Turn on your router and locate the WPS/Reset button on the back panel. Press and hold this button for more than 5 seconds to reset the router to its factory default settings. Visit http://tplinkwifi.net to create a new login password.
FirmwareFirmware link
Default usernameN/A
Default passwordYou set it at http://tplinkwifi.net
Default IP address192.168.0.1