Microsoft Exchange is a standard groupware platform in many corporate environments, but it needn't be limited to just Windows.
If you're working in a corporate environment, the chances are that you or your colleagues use Microsoft Exchange for tasks such as sharing of calendars, documents and the global address list. Such is the importance of these Exchange-only features that I've witnessed several Linux-based offices running extra Windows/Mac PCs solely for this purpose. The applications I'll be covering here bring Exchange functionality to the Linux desktop, so you can say good riddance to that Windows PC or put it to better use - like a doorstop.
Ximian Evolution Connector
Ximian Evolution is one of the premier e-mail clients for the Linux desktop. Evolution is a core component of GNOME and is included in almost every Linux distribution. If you've just jumped aboard Linux from Windows, Evolution has a similar look and feel to Microsoft Outlook, making it an easy application for first timers to pick up.
Recently, Ximian was acquired by Novell. Shortly after the acquisition, the Ximian Evolution Connector - a product which brings full Exchange functionality to Evolution and previously cost $US69 - was made freely available. The Connector is distributed as a separate package to Evolution, which seems a little strange now that it's available freely, but there you go.
Installing the Connector from source is quite difficult. Like many GNOME applications, the source dependency tree required by the Connector is huge and often very hard to satisfy from a standard Linux distribution. I have included the pre-built versions of the Connector for a number of distributions on this month's cover CD, as well as some third-party RPMs for Fedora. If your distribution is not included, I recommend you search for a pre-built version of the Connector before attempting to compile it yourself.
After the Connector is installed, restart Evolution and a new account type named 'Exchange' will now be available. Once you've created an account, all the Exchange features are available from the folders sidebar, just like in Outlook. I was able to migrate my existing Exchange account to Evolution with no problems at all. After migrating, Evolution is essentially a drop-in replacement for Microsoft Outlook, both graphically and feature-wise. The Connector works really well, even supporting the more advanced Exchange features such as granting access to calendars through delegation.
If you use KDE, the KOrganizer utility now includes support for Exchange 2000. KOrganizer, as the name implies, is a stand-alone calendar and task-list application. To configure KOrganizer for Exchange, first turn on the Exchange plug-in in the Settings-Configure Plug-ins menu. Once the plug-in is turned on, there will be an Exchange menu item available. Select Configure from this menu and enter your account details. I found it's safe to leave the port entry empty; the plug-in will connect to the default port.
KOrganizer works well, but there are a few caveats. I encountered problems that looked to be time zone related when I first connected, causing calendar items to appear at the wrong time of day. Using KOrganizer is also little cumbersome, as it only synchronises with the Exchange server when a download command is issued under the Exchange menu. Obviously, this is a hassle if you have other people updating your calendar for you. The level of support is nowhere near the level of Evolution, but if you're a fairly light user of Exchange, KOrganizer handles the standard functions well.
The best way to ensure 100 per cent compatibility with Exchange/Outlook features is to run Outlook itself. Crossover Office from Codeweavers (http://www.codeweavers.com) allows you to do just this. Crossover Office is a version of the open source utility, WINE (http://www.winehq.com), which has been customised to run a number of commercial productivity packages such as Microsoft Office. The product costs $US39.95 for a single license. A free 30-day trial is also available for download from http://www.codeweavers.com/site/products/download_trial. The Windows emulation is not yet perfect - pauses and small graphical glitches sometimes occur - but crashes are infrequent and the overall performance of Outlook is good.
If the price of Crossover Office is too much for you, you can always try WINE itself. The stability and compatibility of WINE can vary a lot between versions, so if Outlook fails to work with the latest version, try an earlier release. The WINE Web site includes an application database (http://www.winehq.com/site/supported_applications) which is full of useful tips on getting applications to run with specific versions of WINE.
So far we've looked only at alternative clients for Microsoft Exchange. What about replacing Exchange completely?
Bynari Insight Server & Connector (http://www.bynari.net/) is a commercial e-mail and groupware server designed as an exchange replacement. Unfortunately, Bynari requires a plug-in to be installed on each Outlook client, adding some administration overhead to any migration. Insight is based on a number of open protocols such as LDAP and IMAP and will work easily with all Linux clients. A 30-day free trial of the server is available from the Bynari web site.
OpenGroupWare.org is, as the name implies, a project that aims to build an entirely open source groupware server. Connecting Outlook to OpenGroupWare also requires a plug-in named ZideLook, developed by one of the major commercial backers of the project (Skyrix Software, http://www.skyrix.de). Unfortunately, while OpenGroupWare is entirely open source, the ZildLook plug-in is proprietary. If you're wanting to try out OpenGroupWare, a bootable KNOPPIX CD is available from the OpenGroupWare Web site containing a working server. With this CD, all you need to do is reboot your computer and you're up and running with OpenGroupWare.
Distribution vendor SUSE, which, like Ximian, is owned by Novell, also produces an Exchange replacement named OpenExchange (http://www.suse.com/us/business/products/openexchange/). OpenExchange takes an interesting route and includes a complete Linux operating system on its installation CDs. As a consequence, OpenExchange cannot be installed on an existing server. As with both Bynari Insight and OpenGroupWare, connecting to OpenExchange from Microsoft Outlook requires a plug-in. OpenExchange also features an excellent Web interface, which is available in demo form at http://www.suse.com/us/business/products/openexchange/demo.html.
To be a viable replacement for Exchange in most environments, a server should support the Exchange protocols so that no extra configuration needs to be performed on client computers. It seems that, if you want to migrate away from Exchange right now, you'll need to update each of your clients running Outlook, or migrate away from Outlook before considering replacing Exchange.
Extra SoftwareIn recent times, standard Linux distributions have grown massively in size. Four or more CDs of software are included with many and yet, somehow, this is not enough. A huge number of programs get left out of distributions, either due to licensing or space considerations. If you want to add Evolution Connector to your computer, for example, it would be great to find a version for your distribution. When looking for such a program, try http://rpm.pbone.net/ and http://freshrpms.net/, these are two excellent resources for third party versions.