Kerio MailServer 6.4.1 review

Kerio has made a point of marketing its MailServer product as an alternative to Microsoft’s Exchange Server. But, as a mail server in the small- to medium-sized enterprise market, it’s also up against products from Ipswitch and Gordano. However, it offers a number of useful facilities that make it an attractive proposition in its own right. Apart from its comprehensive mail-handling facilities, it offers collaborative groupware facilities, including shared calendars and tasks, and shared address books that can be accessed from a web interface or from a suitable client such as Outlook or Entourage.

Kerio offers simple integration with Microsoft Outlook clients, including Outlook 2007. The web interface provides similar facilities and could easily be used as an alternative. Laptop users may even find it more useful, although it does require access to the internet. A second web interface is provided for users accessing the service from a PDA.

An important new feature is the software’s ability to operate with a wider range of mobile devices. As these become more capable and powerful, the ability to synchronise with them is much more useful to staff out on the road. To this end, Kerio now offers support for mobile devices, such as the BlackBerry and Symbian-based devices, and can synchronise with devices running Microsoft’s Mobile Outlook under Windows Mobile 5. The BlackBerry option also requires Notify’s NotifyLink software (www.notifycorp.com) to provide the necessary communication features.

The software includes McAfee antivirus as standard. It can also use a second antivirus engine for further protection. Most well-known products from suppliers such as Sophos, Grisoft and Symantec are supported, as well as the open-source ClamAV. Email is scanned both inbound and outbound, and internal mail is also scanned to prevent infection within the LAN. Infected mail may be disinfected or quarantined.

Antispam facilities are comprehensive. SpamAssassin is provided along with the usual Realtime Black List (RBL) and Bayesian analysis engine options. Customised rules can also be created to cope with spam that may arrive from other sources not listed in the RBL. SpamRepellent can help to confound automated spam senders by delaying response times. Further antispam measures include both Microsoft’s Caller ID and Sender Policy Framework and sender domain verification, as well as limiting concurrent connections from any mail server.

We installed the software on a small server equipped with an Intel Pentium 4 processor and 1GB of RAM running Microsoft Windows Server 2003 SP1. Setup was straightforward. The installation process offers the opportunity to import user lists from a variety of sources including CSV files and Windows Active Directory, and can use either Active Directory or its own internal user database to validate users.

We tested it using a software program that sent a wide selection of mail to a number of test mailboxes. We mixed a number of spam messages into the message stream and included the EICAR virus test as an attachment in some cases. We also injected false and empty return addresses. Kerio’s MailServer proved to be effective and handled the automated tests well.

Kerio MailServer is simple to set up and use, and would be a good choice for the smaller organisation with neither the time nor the resources to spend on the more powerful Microsoft Exchange software.