Improving the OWA Experience

Outlook Web Access (OWA) is a terrific way to provide email access to users who can't (or don't want to) use Outlook as their email client. For example, OWA makes a terrific solution when coupled with factory-floor kiosks; Macintosh users can use OWA to get full calendaring access without running the clunky Microsoft Outlook:mac 2001 client; and UNIX users can access OWA from any Web browser. However, few things in life are so good that they can't stand improvement, and OWA is no exception. Let's examine a few steps that you can take to improve your end users' OWA experience.

Probably the most common question about OWA 2000 and OWA 5.5 is how to add a spell-checker. OWA 2003 will include a slick spell-checker, but for earlier OWA versions, you can look into third-party products such as Messageware's Plus Pack for Outlook Web Access ( http://www.messageware.com ) or Rupp Technology's AutoSpell for Outlook Web Access ( http://www.spellchecker.com ).

As far as performance is concerned, OWA 2000 is both faster and more efficient in its use of bandwidth than OWA 5.5 is, but OWA 2000 takes a long time to load the initial page. This lag is a result of all the little toolbar icons and graphic gadgets that give OWA 2000 its Outlook-like appearance. (OWA 5.5's simple interface doesn't have this problem.) You have several options to speed up OWA 2000's initial page load.

The first method is simple. By default, Microsoft IIS includes a header with OWA 2000's image files; this header tells receiving systems not to cache those image files. This instruction forces the client to refetch the initial page each time a user opens OWA. To speed load times, open the Microsoft Management Console (MMC) Internet Services Manager (ISM) snap-in on your OWA 2000 server, navigate to the Default Web Site/Exchweb/Img directory, and open the directory's Properties dialog box. Go to the HTTP Headers tab and clear the Enable Content Expiration check box. This action marks the images to never expire. If you want the images to expire from the cache periodically, select the check box but use the Expire After control to specify an expiration period.

The second method is also simple to implement but is more restrictive for users than the first method is. OWA 2000 comes in two flavors: a rich client, which takes advantage of dynamic HTML and other features that Microsoft Internet Explorer (IE) 5.0 and later support, and a reach client, which works with almost any HTML 3.2-compliant browser (including browsers for Linux, Mac OS, UNIX, and even OS/2). The rich client has a more flexible and useful interface but is slower than the reach client. OWA typically performs server-side client detection to determine whether a requesting client can support the rich client. However, in Exchange 2000 Server Service Pack 2 (SP2) and later, you can force OWA 2000 to use the reach client only. (See the Microsoft article that's listed in the Resources section below for information about how to apply this change.) Doing so removes a great deal of functionality for users whose machines support the rich client but noticeably speeds up those users' OWA sessions.

To further improve your OWA end users' experience, you can customize OWA--for example, you can change OWA's appearance to match that of your company's other Web sites. OWA 5.5 works as a set of Active Server Pages (ASP) files, so if you know how to edit those files, OWA 5.5 is easy to customize. You can also customize OWA 2000 to some extent, although doing so isn't for the faint of heart. The Microsoft Exchange Online Book "Customizing Microsoft Outlook Web Access" ( http://www.microsoft.com/downloads/release.asp?releaseid=44276 ) will help you get started. Be forewarned, though, that you might need to redo any customizations if you migrate to Exchange Server 2003.

Of course, the most important area in which you might want to improve any Web-based product is security. Next week, I'll examine some of the security improvements that you can expect to see in OWA 2003.