Eu recomendo começar com este guia na lista de discussão da Apple (crédito para Gilbert Palau):
O ponto crucial é citado aqui:
- Go to the Directory Utility ‐> /Applications/Utilities/
- Click the Advanced Settings Button ‐> Buttons should appear on the top
- Click Services
- Make sure you're authenticated to makes changes ‐> click the lock and login
- Double‐click the Active Directory
- type in your domain in "Active Directory Domain" ‐> ex. (mydomain.com) watch out if your domain ends with .local opposed to.com or .net, you need to disable bonjour if it ends with .local.
- click bind
- enter in username and password ‐> just the username NOT email@hidden or MYDOMAIN\User
- Click ok.