I try follow the step to reset default but it doesn't apply.
1) After connecting the serial cable to switch and system you’ll need to open a program such as Hyperterminal or Putty and enter the following settings:
- Bits per second: 38400
- Data bits: 8
- Parity: None
- Stop bits: 1
- Flow Control: None
2) Connect power to the switch. After a couple of seconds you should see the prompt ‘Autoboot in 2 seconds – press RETURN or Esc. to abort and enter prom.’
PRESS Esc at this point – a second too soon, or a second too late and you’ll miss it. It’s a case of fastest reactions win!
3) The menu (shown below) will open – select option 3 to reset the password to null and then select option 5 to exit and continue the boot sequence
4) Once the logon prompt appears enter the username admin and leave the password field blank (either from the console or web interface)
5) Change the password to the desired setting