Hard reset D-Link DIR-645

Factory reset (Hard reset) The factory reset button hole is located on the bottom of the router – check the picture above. Power ON the router. Use a thin object (paperclip) to press and hold down the button for 10 seconds. Release. Wait about 30-60 seconds before accessing the router.
Firmware Firmware link
Default username admin
Default password [leave blank]
Default IP address 192.168.0.1