I have 2 Netgear FSM726V1 managed switches that I could do anything with because I didn't have the Terminal User password or the Enable password, and after about two weeks of digging around the internet I managed to find the following set of instructions which worked for me and I now have two switches I can configure.
You need to
interrupt the boot sequence and use a hidden system command to disable the password for the switch on reboot.
- Power on switch, press "ESC" key very quickly to go to Mini Boot Monitor mode. (If you press too late you will go into the option to boot from Flash or Net via TFTP.)
- Press "Enter" key.
- At the commend prompt Type: . EmergencyPasswordReset (Exactly as written it is case sensitive and doesn't like spaces. This is a hidden command.)
- There is then a question . "Are you sure? (y/n)". The answer is "X". This is a capital X - It will disable the switch password for the default admin user.
- You will get a response that the system password has been disabled - if you don't get this confirmation it hasn't worked because you have mistyped something but it won't tell you that.)
- Enter "g" to reboot.