Hello @Dan67,
let's first take a look what happened initially.
The reason that you could suddenly no longer log into the switch is probably due to password aging which has a default setting of 180 days. You can find more details about this in the following document:
Configure Password Strength and Complexity Settings on the Cisco Business 250 or 350 Switch
Secondly, there was no need to do a factory reset because these switches support password recovery via the CLI.
This feature allows you to configure new passwords without loosing your config, unless you configured the 'no service password-recovery' command on your switch.
There is a video from Cisco Tech Talk that shows step-by-step how this password recovery is done:
https://www.youtube.com/watch?v=NBq5AIE8plI&t=1s
However, since you already tried a factory reset you now have to do the manual steps via the Reset button:
- Disconnect all Ethernet cables from the switch.
- Press and hold the Reset button on the switch using a pin or paperclip for 15 to 20 seconds.
- Release the Reset button once all the port LEDs light up.
This indicates the switch has been reset to factory defaults.
- After the reset, Telnet and SSH services are disabled by default.
You will need to connect your computer directly to the switch using a serial console cable.
- Log in to the switch console using the default username and password:
- Username: `cisco`
- Password: `cisco`
- You will be prompted to configure a new password for security purposes.
After a factory reset you can only connect to the switch via CLI.
Other options like Telnet/SSH or HTML do not work until you completed the basic configuration via CLI.
HTH!
