Microsoft 365


Active Directory


Windows Server



Exchange Server

Configure OMA in Exchange 2003

Daniel Petri


How can I Configure OMA in Exchange 2003?

One of the coolest things in Exchange Server 2003 is it’s ability to allow mobile users to connect to it via a stripped down version of Outlook Web Access called (you guessed right) “Outlook Mobile Access”, or OMA for short.
Exchange Server 2003 enables any device capable of running the Windows Mobile 2002 or later, such as browser-enabled cell phones or Windows Mobile–based Personal Digital Assistants (PDAs) to access corporate Exchange information. All changes made on the wireless device are reflected in the live mailbox and can be seen from a full desktop mail client such as Outlook 2003 or Outlook Web Access (OWA).
The best thing about OMA is that it is practically configuration-free. almost nothing to worry about and no buttons to click. Just install Exchange Server 2003 and you’re almost ready to go.


In order to successfully implement OMA on your organization you need the following:

Lamer note: Make sure you have all things set up and that your Exchange organization is flawlessly working. We do not want to blame OMA for messing up your settings, because it won’t.
Pre-SP1 installations of Exchange Server 2003 required that you install .NET Framework 1.1 Device Update 4.0. If, for some strange reason, you do not want to install SP1 for Exchange, make sure your install DUP. SP2 does not require any additions.
Any mobile phone or mobile device–based browsers that support HTML, XHTML, or Compact Hypertext Markup Language (cHTML) can be used to connect to OMA. For a list many supported devices click HERE.

Enabling OMA

As stated above, you actually do not need to install anything to get OMA up and running.

  1. Open the Exchange System Manager.
  2. Navigate to the Global Settings folder, expand it and go to Mobile Services. Right-click Mobile Services and choose Properties.
  3. In the Mobile Services properties window, under Outlook Mobile Access, click to select the Enable Outlook Mobile Access and the Enable Unsupported Devices check boxes.
  4. Click Ok.


Firewall and Internet connection

I won’t go into detail here, but you should make sure that your Firewall allows TCP Port 80 and 443 (optional) to your server (the Exchange server that holds the OMA site) and to the following URL: http://FQDN/OMA (replace FQDN with the Fully Qualified Domain Name of your server).
In cases where your organization uses a Front-End/Back-End topology, you should allow access to the Front-End server(s).

SSL and security

You can protect the OMA traffic by using SSL. Read the following article on how to do that: Configure SSL on OMA.

Enabling/Disabling per user settings

By default, all mailbox-enabled users have OMA enabled. If you want, you can disable OMA on a per-user basis, while retaining the OMA functionality for other users.
Do disable (and later enable) a specific mailbox-enabled user from using OMA perform the following steps:

  1. On your Exchange server, open Active Directory Users and Computers.
  2. Navigate to (or find) the required user account.
  3. Double-click the required user account, or right-click it and select Properties.
  4. Go to the Exchange Features tab, select Outlook Mobile Access, and press the Disabled button.
  5. Click Ok all the way out.

To re-enable OMA for the specific user, reverse your actions.

Test OMA

You should now Test OMA in Exchange 2003 from a regular web browser (just to see that it’s working), from any Pocket Explorer or WAP browser emulator (as I did with the following screenshots) or from your mobile phone/Pocket PC/Palm OS.
Provide your username and password:
Begin browsing your mailbox:

Working with OMA

As with Outlook Web Access (OWA), as long as you maintain a connection to your server you can browse and work with your mailbox.
Most settings and options are self explanatory, such as browsing the folder tree:
Answering mail:
and more.

Related articles

You may find these related articles of interest to you:

Article saved!

Access saved content from your profile page. View Saved