It sounds like your users log on locally on the workstations. When they do that, they don’t belong to the “users”-group in Active Directory. You could map the drive and specify a user account to use for the authentication. If it doesn’t work, you could also map a network printer on the Active Directory Server, where you specify a user account with a password. It will then authenticate the user whenever the user logs in and reconnects the printer. If your user do log in on the Active Directory Domain, you should check the security policy, so that users have permission to map network drives.