Hard reset TP-LINK TL-WR1042ND

Factory reset (Hard reset) Power the router ON and locate the reset button-hole on the rear panel. Use a pin to press into the hole and hold for (at least) 5 seconds. Release and wait for a minute until the reboot process is over.
Firmware Firmware link
Default username admin
Default password admin
Default IP address 192.168.1.1