Chapter 7: User and Contact Administration

One of your primary tasks as a Microsoft Exchange administrator is to manage user accounts and contacts. User accounts enable individual users to log on to the network and access network resources. In Active Directory, users are represented by User and InetOrgPerson objects. User objects represent standard user accounts; InetOrgPerson objects represent user accounts imported from non-Microsoft Lightweight Directory Access Protocol (LDAP) or X.500 directory services. User and InetOrgPerson are the only Active Directory objects that can have Exchange mailboxes associated with them. Contacts, on the other hand, are people that you or others in your organization want to get in touch with. Contacts can have street addresses, phone numbers, fax numbers, and e-mail addresses associated with them. Unlike user accounts, contacts don't have network logon privileges.

Understanding Users and Contacts

In Active Directory, users are represented as objects that can be mailbox-enabled or mail-enabled. A mailbox-enabled user account has an Exchange mailbox associated with it. Mailboxes are private storage areas for sending and receiving mail. A user's display name is the name Exchange presents in the global address list and in the From text box of e-mail messages.

Another important identifier for mailbox-enabled user accounts is the Exchange alias. The alias is the name that Exchange associates with the account for mail addressing. When your mail client is configured to use Exchange Server, you can type the alias or display name in the To, Cc, or Bcc text boxes of an e-mail message and have Exchange Server resolve the alias or name to the actual e-mail address.

Although most Microsoft Windows user accounts are mailbox-enabled, user accounts don't have to have mailboxes associated with them. You can create user accounts without assigning a mailbox. You can also create user accounts that are mail-enabled rather than mailbox-enabled, which means that the account has an off-site e-mail address associated with it but doesn't have an actual mailbox. Mail-enabled users have Exchange aliases and display names that Exchange Server can resolve to actual e-mail addresses. Internal users can send mail to the mail-enabled user account using the Exchange display name or alias, and the mail will be directed to the external address. Users outside the organization, however, can't use the Exchange alias to send mail to the user.

It's not always easy to decide when to create a mailbox for a user. To help you out, consider the following scenario:

1. You've been notified that two new users, Elizabeth and Joe, will need access to the domain.

2. Elizabeth is a full-time employee who starts on Tuesday. She'll work on-site and needs to be able to send and receive mail. People in the company need to be able to send mail directly to her.

3. Joe, on the other hand, is a consultant who is coming in to help out temporarily. His agency maintains his mailbox, and he doesn't want to have to check mail in two places. However, people in the company need to be able to contact him, and he wants to ensure that his external address is available.

4. You create a mailbox-enabled user account for Elizabeth. Afterward, you create a mail-enabled user account for Joe, ensuring that his Exchange information refers to his external e-mail address.

Mail-enabled users are one of several types of custom recipients that you can create in Exchange Server. Another type of custom recipient is a mail-enabled contact. You mail-enable a contact by specifying the external e-mail address that users can use to send e-mail to that contact.