I found a printer Maintenance Manual page and there was an instruction on how to unlock the admin password. I don't remember what this page is and what the keyboard shortcut was, I think it won't be a problem to find it.
The discussion revolves around resetting the administrator password for the OKI B412 printer, as the default password 'aaaaaa' is not functioning for some users. It is suggested that the correct password may be the last six characters of the printer's MAC address, although this has not worked for all. Users are seeking methods for a factory reset or alternative ways to regain access. A maintenance manual is referenced, which may contain instructions for changing the password. The factory login details are confirmed as username 'root' and password 'aaaaaa'. Summary generated by the language model.
