We have a mixed environment of Exchange 2007 for faculty & staff and Google Apps for students. Students do not have AD accounts so in order for routing to occur all of our students are mail contacts in AD. The contact consists of their alias and an external address. When an outside or internal user emails a student the AD contact has the external email address set to their Google Apps account and the mail is delivered there. Everything works just fine. Reading the book "Exchange Server 2007 Administrator's Pocket Consultant" on page 151 it states: "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." Reading the last line it sounds as if what we are curently doing isn't supposed to work with Exchange? Am I reading this wrong or is it just a mistake in the book? Todd

People outside your AD aren't e-mailing the Exchange contact, so I'm not sure what you mean. You likely have an SMTP alias for their domain address.

Yes, their contacts include our domain address as we as their external address. For example assuming our domain is foo.bar a user would have in their AD Contact user@foo.bar and user@hotmail.com. Since foo.bar is included in their contact is that why it is possible for users outside of our organization (the Internet) to be able to send mail to these contacts which would then end up at hotmail.com? I guess the wording of the text I quoted stumped me.

Hi Todd, Please let me know whether you have configured hotmail.com as accepted domain. If you have, the message will be received and forwarded according to your configuration. By default, Exchange should reject message which send to hotmail.com as unable to relay from external anonymous sender. Mike

Hotmail is not an accepted domain however the contact also has our domain name as an email address which is why it is working. The quote from the book threw me. Users on the outside are emailing our domain which the contact is forwarding out.

Hi Todd, For external user,they have to send email to user@foo.bar. If they send email to user@hotmail.com, the Exchange Server will reject the email due to email unable to relay. After Exchange received the email, it will resolve the user@foo.baraddress into user@hotmail.comif the user@hotmail.comis the primary Email Address. For internal user, they are able to send email to user@hotmail.comdirectly after authenticating to Exchange Server if they use POP3/SMTP account. If the user use Exchange account Outlook, the message submitted by using LegacyExchangeDn of the user. Then, Exchange Server will resolve the LegacyExchangeDninto primary email address of the user. Mike