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Outlook 2007 vs. Outlook 2003

New and improved features make all the difference

Executive Summary:

If you’re migrating from Microsoft Office Outlook 2003 to Microsoft Office Outlook 2007, you need to up-to-date on all of Outlook 2007’s new features, including those that work only if you’re also using Exchange Server 2007.

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Do you remember the first time you purchased a software application upgrade, only to discover that you’d wasted your hard-earned money on a few new bells and whistles that you didn’t even need or want? I remember the first time this happened to me—and the many times since then. Those experiences have made me leery about purchasing new software if the version I’m using is working just fine. For years, I kept using Microsoft Office 2000 or Microsoft Office 97/98, even though I had a perfectly good copy of Microsoft Office XP waiting to be installed. “No thanks,” was all I could think whenever I looked at that box.

But when Microsoft Office 2007 was released, I was excited about the applications’ nifty new ribbon interface. So I was a bit put off when I opened Microsoft Office Outlook 2007 for the first time and didn’t see the ribbon. I wondered, “How is this any different than Microsoft Office Outlook 2003?” Over time, I’ve found several differences between Outlook 2007 and Outlook 2003. Depending on your use of Outlook, some of those differences can be substantial.

Exchange Server administrators wear many hats, including that of Outlook instructor. Therefore, administrators who migrate to Outlook 2007 need to be up-to-date on all the new features—both for their own benefit and so they can help users.

Outlook 2007 and Exchange 2007 Combo Features
Some of Outlook 2007’s features work only if you’re also using Exchange Server 2007, which might be a consideration if you’re trying to decide whether to upgrade from Outlook 2003. If you don’t have any immediate plans to also move to Exchange 2007, you might not need Outlook 2007.

According to the Microsoft Exchange Team Blog (, the following features are available in a combined Outlook 2007 and Exchange 2007 environment:

  • Autodiscover—This feature is automatically added with the Client Access Server (CAS) role installation. A virtual directory is created for Autodiscover, along with a Service Connection Point (SCP) object within Active Directory (AD). The SCP object helps users who are logged on to the domain locate the URL for the service on the CAS server, whereas a DNS server helps users who aren’t on the domain locate the service. The information that gets pushed down to clients includes the mailbox server where their mail resides, the unified messaging (UM) server (if applicable), Offline Address Book (OAB) download location, URLs for the Availability service and Out-of-Office, the authentication method, and Outlook Anywhere configuration. For more information about the Autodiscover service, see the Microsoft white paper “Exchange 2007 Autodiscover Service” (
  • Web-based OAB—This feature assists with public folder depreciation in Exchange. Public folders are the standard method Outlook clients use to access the OAB. If your organization doesn’t use public folders, clients can use Web distribution to access the OAB through the CAS. Background Intelligent Transfer Service (BITS) technology is used to download updates from the OAB to clients.
  • Availability Service—Previously known as free/busy information, this service looks at your calendar and calculates the amount of time you have scheduled or free for scheduling. You locate this service through the Autodiscover service, which provides a URL that points to the Availability service.
    Resource Assistant—This feature lets you book conference rooms and times based on others’ availability, which you can obtain through the Availability service.
  • Unified Messaging—Although you don’t need to use Outlook 2007 to take advantage of UM features, Outlook is the leading application designed to work with UM in Exchange 2007. You can use older Outlook clients, but all the voicemail options aren’t available with legacy clients. You can also use ActiveSync-enabled mobile users, Outlook Web Access (OWA), and/or phones to access UM services.
  • Out-of-Office Assistant—In Outlook 2003, you must manually turn off the Out-of-Office Assistant (although you’re given a reminder). Outlook 2007 lets you schedule times for the Assistant to be on or off. You can also create auto-replies for internal and external emails, as Figure 1 shows. In addition, you can use Rich Text Format (RTF) for auto-replies. Note that if you’re using Exchange 2007 but haven’t yet moved to Outlook 2007, you can use OWA to configure the Out-of-Office Assistant’s new features. Even though the Outlook 2003 client doesn’t provide the ability to set up multiple Out-of-Office messages, OWA on Exchange 2007 lets you do so.
  • Managed Folders—One of Exchange 2007’s more interesting features is the ability to manage default and custom folders. You can enforce specific policies on users’ default folders; for example, you can permanently delete items in the Deleted Items folder after a specified number of days. You can also create folders within a user’s Inbox (without the user’s permission) and use policies to enforce rules on those folders.
  • Increased Rules Limit—Previous Exchange versions have a 32KB limit for email rules connected to a mailbox. In some cases, users will receive an error message saying that their rules can’t be uploaded to the Exchange server because of insufficient space to store all the rules. This limit has been increased to 64KB by default. In addition, you can use PowerShell to increase the limit as high as 256KB.
  • Partial Item Change Download—Outlook’s Cached Exchange Mode feature, which I discuss in the following section, tracks changes made to messages and message properties. In earlier Outlook clients, if a property is changed, the entire message has to be resynchronized to the client. But in Outlook 2007, messages are broken into sections; if a change is made to one section, then only that section is redownloaded.
  • Message Classification—Message classifications are important because sometimes you need to tag a message with information that explains the purpose of the message or its intended use. Exchange 2007 includes several default classifications, such as Attorney/Client Privilege. You can also create additional classifications.

If you’re considering an upgrade to Outlook 2007 to take advantage of one of these new or enhanced features, you need to know which features work only in combination with Exchange 2007. And if you’re starting to get the uneasy feeling that the only way to get all the bells and whistles of Outlook 2007 is to run the program on a Windows Vista machine connected to an Exchange 2007 server—you’re right! Which isn’t necessarily bad, but it might help you determine whether upgrading to Outlook 2007 is right for your organization. For an in-depth comparison of OWA 2007 with SP1 on Exchange 2007, OWA 2007 without SP1, Outlook 2007, and Outlook 2003, see the feature comparison table at the Microsoft Exchange Server Web site (

Other New and Improved Features
Not every new Outlook 2007 feature is Exchange 2007-dependent. When you open Outlook 2007, one of the first differences you’ll notice is the To-Do Bar, which Figure 2 shows. If you’re like me, you spend most of your time in Outlook in the Mail view. The To-Do Bar lets you stay in the Mail view and still see a calendar (or multiple calendars), current tasks, and flagged messages for follow-up (as opposed to using Outlook 2003’s For Follow Up folder).

Another difference, and a huge plus in Outlook 2007, is the ability to preview attachments. Sometimes you receive documents that you don’t necessarily need to open, just give a quick scan for the information you need. Previewing attachments rather than opening them saves time and increases your productivity. This feature also improves security because you aren’t opening as many documents. The preview feature shows you a document but doesn’t expose your system to any harmful elements (e.g., viruses, macros) because attachments are placed in a securetemp folder. Both Outlook 2007 and Outlook 2003 have a Cached Exchange Mode that you can enable to ensure your previews are “downloaded” ahead of time, including headers, text, and attachments. According to the Microsoft Office Outlook Team Blog (, “Outlook can preview many common types of files. Images work great, as do files created in Word, Excel, PowerPoint, and Visio. If you are using Windows Vista you can also preview audio and video files. With Adobe Reader 8.1 installed, you can even preview PDF files. Many previewers allow you to interact with the attachment in some basic ways. For example, the PowerPoint previewer lets you advance through each of the slides in the PowerPoint file, all without leaving Outlook!”

Another of Outlook 2007’s benefits is the new Instant Search feature, which indexes your mail to let you quickly locate your data. Because users are constantly asking for larger mailboxes, and because Exchange supports them, mailboxes have increased in size. Larger mailboxes make it harder for users to find old email messages. Instant Search works on both Vista and Windows XP systems, but you need to install the Windows Desktop Search tool for optimal performance on XP. The jury is still sort of out on the Instant Search feature, because not everyone is running Vista with Outlook 2007 or wants to install the Windows Desktop Search tool—so depending on your setup and the tools you use for indexing mail, you might not be impressed with Instant Search.

The ability to share your calendar is an improved rather than a new feature. Although Outlook 2003’s calendar sharing works fine, Outlook 2007 provides more features. For instance, a cool new feature is the ability to overlay your calendar and others’ calendars that are shared with you. Outlook 2003 lets you view calendars side by side, but Outlook 2007’s overlay effect lets you more easily see how your schedule matches up with others’. When you’re trying to determine the best time for a meeting, you can use the overlay to quickly see schedule conflicts. And because you can configure resource mailboxes for your resources (e.g., meeting rooms, projection equipment), you can also see those resources’ schedules.

Another advancement in the calendar sharing feature is that Outlook 2007 lets you send an HTML snapshot of your calendar to people inside or outside your company. So if you don’t want to share your calendar with someone but you want to give them a quick look at your schedule, you can send them a snapshot. Keep in mind that the snapshot won’t update automatically with your real calendar as you make changes, because no link exists between them. You can also use an Internet Calendar Subscription site to publish your calendar to the Internet and subscribe to others calendars. For example, Office Online ( hosts your calendar through your Windows Live ID account.

Rants? Or Rave Reviews?
Bashing a new application or OS is easy, as you can see from all the online commentaries. But it’s unfair to criticize Outlook 2007 without considering all its new features, the factors that influence those features’ implementation, and the related hardware and software costs.

Personally, Outlook 2007 is the first new release of Outlook that I’ve installed on my production system since Outlook 2000—which is a pretty strong recommendation. However, keep in mind that I’m also using Vista and Exchange 2007 and that I write technical articles and teach about the latest technology.

I’m curious about why others are moving to Outlook 2007. Is Outlook 2007 right for your environment? How do you plan to implement it? What features will most benefit your organization? Or, why isn’t Outlook 2007 right for your environment? Which options is it lacking? Please send me your opinions; I look forward to hearing your feedback.

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