Looking for a simple yet scalable alternative to Microsoft Exchange Server? I recently tested Kerio MailServer 6.1 and found it to be a viable option.

Unlike Exchange and other mail servers that target the small-to-midsized business (SMB) market, Kerio MailServer 6.1 provides multiplatform support. The product can run on Windows Server 2003, Windows 2000 Server, Windows XP, Win2K Professional, Red Hat Linux, Novell SUSE Linux, and even Macintosh OS X. (Running on Windows, the product has modest server requirements of a 500 MHz CPU and 256MB of RAM.) Kerio MailServer can integrate with Active Directory (AD) or Apple's Open Directory, or you can manage users through Kerio's built-in user-administration tools. And Kerio MailServer supports POP3 and secure POP3, IMAP 4 and secure IMAP 4, Kerio WebMail, Messaging API (MAPI), and wireless access through Research In Motion's (RIM's) BlackBerry devices. (The product doesn't provide Instant Messaging—IM— support.)

I tested Kerio MailServer on an unassuming white-box server with a 1.8GHz CPU, 512MB of RAM, and 120GB of storage, running Windows 2003 Standard Edition. The fuss-free installation process took just a few minutes to install both the mail server and the Administrative Console, which Web Figure 1 (http://www.windowsitpro.com, InstantDoc ID 48792) shows. You can use the Administration Console to add email users, perform email backups, configure email settings, and start or stop installed services. Kerio also provides a Web Administration tool for Web-based management.

Aside from supporting several popular external antivirus plug-ins, Kerio MailServer is available in a version that comes with McAfee Anti-Virus. Antispam tools include SMTP authorization by user or IP address and support for real-time blacklists (RBLs). Content-based filtering is also available.

Setup and administration was intuitive and easy. However, the product's documentation was better suited to an experienced email administrator than to a novice. The product supports mailing lists, multiple domains, aliases, delivery rules, notifications, and Secure Sockets Layer (SSL)-encrypted email. I especially liked Kerio MailServer's seamless support of the groupware features I'm used to getting from Exchange: calendaring, event notification, shared private folders, tasks, and synchronization to handheld devices for Outlook (by way of Kerio's Outlook Connector), WebMail, or Mac Entourage clients. Kerio also offers an Exchange Migration Tool that you can use to migrate users, messages, attachments, folders, calendars, contacts, and tasks from Exchange.

Kerio MailServer 6.1

PROS: Easy to use; multiplatform support, including seamless support for Outlook and for BlackBerry devices
CONS: No IM capability; documentation isn't well-suited for novices
RATING: 4.5 out of 5
PRICE: Starts at $499 for 20 users (includes 1 year update and technical-support subscription); starts at $899 when bundled with McAfee Anti-Virus for 20 users (includes 1 year update and technical-support subscription); extended subscriptions available
RECOMMENDATION: An excellent choice for SMBs or any business that wants to host its own mail services without dealing with the complexity of Exchange.
CONTACT: Kerio * 408-496-4500 * http://www.kerio.com