Hard reset D-Link DIR-855

Factory reset (Hard reset) This router has a reset “hole” which is located on the back panel (next to the USB port). The router must be switched on. Use a sharp object such as a paperclip to press and hold the button (in the hole) down for 10 seconds. Release and wait about 30 seconds.
Firmware Firmware link
Default username admin
Default password [leave blank]
Default IP address