In case you cannot remember the password for your Cisco device you need to follow the next steps to be able to get pass the user/privileged mode:
1. Reboot your device
2. Ctrl+Break in the first 60 seconds.
3. ROMMON1> confreg 0x2142
4. ROMMON2> reset
5. After the router reboots you should not be prompted for a password. #show running-config is empty.
6. #copy start run
7. After you have copied the startup-config into the running-config you need to change the passwords.
8. #copy run start
9. (config)# config-register 0x2102