Can't log in (iMac)
If the user receives an error message that the username is not found, it likely means they are using the Local login option. Use the Network login button (Windows icon) in the top-right to have the system authenticate them using a Microsoft account. If this is their first time logging into this particular iMac, they may need to validate their login via Microsoft Authenticator.
If the user receives a message that the domain is unavailable or that there is no network connection, disable wi-fi in the top-right. All iMacs on campus should be plugged in via ethernet and will not need wi-fi for any reason.
If the user receives a message that the account is locked out, check to see if the account is locked in Active Directory. If it’s not locked, it means the iMac has temporarily locked logging in with that account. This should be lifted in a few minutes, and can usually be fixed with a reboot as well.