I have tried to reset the password for 7604 but it is not working.
At the rommon mode, i input 0x2142, and then reset.
It reloads and keeps asking for password.
Please take the time to read ALL the document that I've linked before, to the part that says:
The boot sequence is different on the Catalyst 6500/6000 and Cisco 7600 that run Cisco IOS System Software than the Cisco 7200 Series Router because the hardware is different. After you power-cycle the box, the switch processor (SP) boots up first. After a short amount of time (approximately 25 to 60 seconds) it transfers console ownership to the route processor (RP (MSFC)). The RP continues to load the bundled software image. It is crucial that you press Ctrl-brk just after the SP gives over control of the console to the RP. If you send the break sequence too soon, you end up in the ROMMON of the SP, which is not where you should be. Send the break sequence after you see this message on the console:
00:00:03: %OIR-6-CONSOLE: Changing console ownership to route processor
After this point, the password recovery is the same as a normal router.