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Exchange Admin 101: Configuring OMA and ActiveSync

There are two different components used by Exchange 2003's Mobile Information Services: Outlook Mobile Access and ActiveSync. This tip explains how to set up these features.

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Microsoft used to make a product called Mobile Information Server that allowed remote users to access Exchange through devices such as cell phones and PDAs. When Microsoft released Exchange 2003 though, it incorporated Mobile Information Server directly into the messaging server.

There are two different components used by Exchange's Mobile Information Services. The first of those services is Outlook Mobile Access (OMA), which is similar to Outlook Web Access, but with a more simplistic, non-graphical interface.

The other component is ActiveSync. ActiveSync synchronizes a mobile device with a user's Exchange resources (Inbox, Calendar, Contacts, etc.) This allows users to read and respond to e-mail, even when they are offline. The next time a user goes online (or when ActiveSync performs a scheduled synchronization), everything is synchronized. Messages that a user has composed are sent and new messages are downloaded to the mobile device.

Exchange's mobile information services are easy to set up. In fact, much of the configuration is already enabled by default.

Configuring Exchange Mobile Information Services

  1. Open the Exchange System Manager and navigate to Global Settings -> Mobile Services, right click on Mobile Services and select Properties. You'll see that the properties sheet's General tab is divided into two sections: Exchange ActiveSync and Outlook Mobile Access.

  2. In the ActiveSync section, there are three checkboxes, all of which are selected by default. These checkboxes control ActiveSync's behavior. In most cases, you will want to leave these checkboxes selected.

  3. The Outlook Mobile Access section contains two checkboxes, neither of which are selected automatically. To make OMA available to your users, you must select the 'Enable Outlook Mobile Access' checkbox.

  4. Once you select 'Enable Outlook Mobile Access,' the second checkbox will become available to you. This checkbox gives you the option to allow the use of mobile devices that Microsoft does not officially acknowledge as functioning with OMA. (There are a lot of unsupported devices that will work just fine with OMA.)

  5. Once you have selected the OMA options that you want to use, click OK and you will be returned to the main Exchange System Manager screen.

  6. Right click on the Mobile Services container and select the New -> Mobile Carrier options.

  7. Fill in the name of the carrier and the carrier's SMTP domain. For example, if you used Sprint PCS as a mobile domain, you'd enter Sprint PCS as the name and as the SMTP domain. When you're done, click OK.

  8. Now all you have to do is to configure the device itself. This basically just involves establishing Internet connectivity.

  9. After doing so, you can access OMA by entering http://server's_IP_address/OMA into the mobile device's Web browser.

Brien M. Posey, MCSE, is a Microsoft Most Valuable Professional for his work with Windows 2000 Server and IIS. Posey has served as CIO for a nationwide chain of hospitals and was once in charge of IT security for Fort Knox. As a freelance technical writer, he has written for Microsoft, CNET, ZDNet, TechTarget, MSD2D, Relevant Technologies and other technology companies.

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