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VisNetic MailServer Supports Sender Policy Framework
New Version Includes Integrated Support For Anti Spam Measure Designed To Block Forged Email Messages

GAYLORD, MI — September 9, 2004 —, an international provider of security and messaging software, announced today the launch of VisNetic MailServer 7.5.3, featuring support for Sender Policy Framework (SPF), a new anti spam measure designed to fight email address forgery.

Using SPF, the Internet domain of an email sender can be authenticated for that sender, thereby discouraging spammers who routinely disguise the origin of their email--a practice known as email spoofing. Under this practice, spammers forge the email header so that the message appears to have originated from someone or somewhere else. Spammers often use spoofing in an attempt to get recipients to open, and possibly even respond to, their solicitations.

“Most email users have seen this type of spam, whether they recognized it as such or not,” said Mike Deerfield, Chief Executive Officer of “Email messages from recognizable and in some cases, even your own domain are accepted by your mail server, pass through spam filters and are delivered to your users’ mailboxes,” Deerfield continued. “Upon closer look however, most users easily determine that message content is nothing more than spam, unauthorized and more to the point, not relevant to your organization. The end result is that organizations that have deployed sophisticated spam filtering capabilities continue to suffer the cost of spam.”

To combat email spoofing, a growing number of organizations are publishing SPF records for their own domains and then using SPF to distinguish forgeries from real email sent by other domains. Published SPF records include attributes that uniquely describe an organization’s mail, including authorized senders and mail server IP addresses. On the receiving end, organizations using SPF verify the authenticity of each sender's FROM email address by performing DNS queries (accessing the published SPF record) to confirm that the sending server is authorized to send mail on behalf of that address.

With integrated support for SPF, VisNetic MailServer 7.5.3 can be configured to automatically verify the authenticity of the Sender’s email address on every inbound email message. “With the power to block email from forged domains, VisNetic MailServer 7.5.3 continues in its evolution as the first Windows-based email server capable of blocking nearly 100% of spam,” said Deerfield. “Adding integrated support for SPF to an anti spam engine that already features Bayesian filtering, SpamAssassin processing and a challenge-response system, places VisNetic MailServer at the forefront in spam blocking capability,” Deerfield concluded.

Additional improvements to VisNetic MailServer’s Instant AntiSpam include:

  • Support for SURBLs (Spam URI Realtime Blocklist) - Unlike the use of RBLs, which filter on the From email address only, SURBLs allow you to filter and block messages based on spam domains that appear in message body URIs (usually web sites), the message bodies.

  • New SpamAssassin rules - A number of new SpamAssassin rules have been added to the existing rules set for more comprehensive spam filtering.

  • Increased user control of Challenge-Response - The Challenge Response database can be separated for individual users, allowing them to maintain settings and black and white lists as well as authorize or delete pending messages.

Pricing and Availability

VisNetic MailServer 7.5.3 is a one-time, license-based software solution. Pricing is based on number of users and is scaled to fit the financial needs of any organization, starting at $360.00 USD for a Pro 12-User license and graduating to $1,950.00 USD for a Pro Unlimited User license. Additional bundle options include the VisNetic AntiVirus Plug-in and VisNetic GroupWare.

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Founded in 1994 and headquartered in Gaylord, Michigan,® is an International provider of Internet software and services designed to meet the connectivity, security and messaging needs of small-to-medium sized businesses and organizations. publishes a leading suite of Internet products distributed via ESD (Electronic Software Distribution) globally through both direct and multi-tiered distribution channels. continues to bring its vision of the Internet to its customers through a range of products including WinRoute Firewall, a flagship Internet sharing solution; DNS2Go®, the company’s dynamic DNS service; Group Mail, a powerful yet simple email marketing tool; Shavlik HFNetChkPro, patch management software; and a newly commissioned family of products, appropriately named VisNetic®.

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