Microsoft Exchange and Blackberry Server Specialists

Internal Email Address for External People

A common request is for an external contractor to be given an email address in your domain, then any email to be sent to the contractor's own email account.

This can be easily achieved using Mail Enabled Contacts.

What Are Mail Enabled Contacts?

These are entries made in active directory that link to email addresses that are outside of your organisation. These contacts will appear in the Global Address List, allowing users to select them and send email messages to them.

Their primary use is for forwarding email from an existing mailbox. You can only select GAL entries when choosing the forward and this is how they are made. It also allows you to add entries to the GAL of people frequently contacted by members of your organisation - such as suppliers and other contacts. 

Using the facility to store and forward email messages is one way of giving the external contractor an email address while keeping a copy of the email received on your system.

Creating a Conventional Mail Enabled Contact

Mail Enabled Contacts are created in Exchange 2007 Management Console.

  1. Start the Exchange Management Console (EMC).
  2. Expand Recipient Configuration, then Mail Contacts.
  3. Use "New Mail Contact" from the Action Pane or right click in the centre column to start the wizard.
  4. Enter the information that is required, including the external email address.

Once created you can hide the Contact from the GAL by enabling the option on the first tab of the Properties of the Contact - "General".

This is particularly useful when forwarding email from an existing mailbox as it stops users from sending directly to the contact instead of the mailbox first.

You can also add this contact to any mail enabled distribution groups you may have - making it useful when configuring pagers and other tools for alerting staff when something goes wrong.

Sending the Email Out Again

If you are not interested in keeping a copy of the email message, and just want to forward the message to the consultant's own email account, then setting up a mailbox is a waste of drive space.

Simply add another email address to the contact and Exchange will send all email straight back out again.

  1. Right click on the contact and choose Properties.
  2. Click on E-mail addresses tab.
  3. Click "New..." and choose SMTP Address.
  4. Enter an address that is internal.
  5. Press Apply/OK.

The account will have two email addresses on it:

user@externaldomain.com
user@internaldomain.com

The internal email address will now be recognised by AD/Exchange and it will accept delivery of the message, before immediately sending it out to the external address.

Risks

There are risks associated with this process.

  • The biggest being email loops.
    If the external consultant forwards his email to his email address on your system then email will bounce between the two. If you are using a contact only, then the remote machine is more likely to fall over before yours. If there is a mailbox on your system then your server is at risk.
  • Similarly you need to be careful that you use a valid email address for the recipient otherwise email loops will occur with the message failed notification.
  • Finally there is the risk of internal material going out to a server that you do not have control over.