How to Reset Cisco 26xx, 28xx Series Router (Password Recovery) | Cisco

Reboot your router and hold CTR+BREAK sequence to enter into Rommon mode. and enter these 2 commands

rommon 1 > confreg 0x2142
rommon 2 > reset

done :)

Now revert your router sequence back to normal:

Router>enable
Router#config terminal
Router(config)#config-register 0x2102
Router(config)#exit

done:)