Outlook - Open Additional Mailboxes

A customer once asked me how to configure Outlook to use mutliple Exchange accounts. They wanted to be able to send email as both their personal account and an admin account. They used MS Exchange 2007 as their exchange server and Outlook 2007 as their exchange client.

When they attempted to add a second exchange account via the Accounts Menu under tools, Outlook advised them that they already had an exchange account created. -- Leading them to conclude it was impossible.

This is a very common scenario so I thought I would create some instructions on it. There is, in fact a way around Outlook's 1 exchange account rule.  While it is true you can only have 1 connection to an exchange email server, this doesn't mean you can't open up mutliple mailboxes which you have permission to. So we simply need to tell Outlook to open up more then 1 mailbox using our username/password.  This obviously assumes you already have permission to both mailboxes with the same username/password that you use to log into Windows.  If not, then your IT person needs to go into Active Directory and grant you those permissions. - I'll cover how to grant an individual permissions to a mailbox in another post.

So here's what to do....

In Outlook 2007, click on Tools | Accounts |
Highlight the exchange account
Click "
More Settings | Advanced (tab)

Under "
Open these additional mailboxes" click Add and type in the first 3 or 4 letters of the 2nd mailbox. Allow Outlook to find the mailbox in the Global Address List. If it doesn't come up, make sure the mailbox you are trying to add is not "hidden" -- this can be checked by someone in IT or by you if you have access to AD Users and Computers snap-in.

Click OK and Next until you get to finish. 

You should now see the new mailbox in your list of folders. It probably appears a just one line so click on the
[+] next to it.

This is assuming you have permission to this mailbox via the same account you log into Windows with...otherwise you will get prompted to enter a username/password. 

Now Open up a blank email, as if you are going to send one. 
Click on
Options and then "Show From
Click the
[X] in the upper right to save the changes.
Now open another new email like you did before and notice that the FROM field is now present.

If you don't type anything in the FROM field, Outlook will always send the email using your primary exchange account, not the additional mailbox you added.
If you have "Send As" rights to the additional mailbox in AD Users and Computers, then you can type its name into the FROM field and send email as that account.

I used this trick when I use to work for a centralized help desk so I could send announcements as the help desk.