A bit of explanation for the uninitiated is in order. An email blacklist is simply a maintained list of full email addresses to which an antispam program refers when scanning incoming email in order to help figure out which messages are spam. An email whitelist is the exact opposite in that it's used by antispam software as a place to store full email addresses of senders whose messages are always permitted. But antispam software, including SPAMfighter and SPAMfighter Pro do more than just maintain good and bad lists. SPAMfighter installations are linked through the Internet to a central server which essentially acts as a blacklist clearing house for all SPAMfighter users. For example, if you and, say, and thousand other SPAMfighter users over a period of a few hours all reject the same piece of junk email, the sender and the domain are automatically blacklisted. The blacklists of all the other SPAMfighter users are then automatically updated to reflect the new spammer. There are other rules and certainly some deeper analysis takes places, but that's basically how the blacklist process works. In addition to that straightforward blacklist approach, SPAMfighter analyzes the pattern and language in newly blacklisted items in order to refine or modify their spam detection algorithms. Obviously, for SPAMfighter and other antispam software companies it's a lot of hard work. Then again, if was easy we'd all be doing it for ourselves.

After a couple of months of use, we observed only a handful of false positives (email incorrectly or unfairly blacklisted) and the inboxes on all five computers used during this review experienced a 95% drop in junk email and outright spam.

Cons: The product registration process is unintuitive and somewhat aggressive. There are simpler ways of doing this sort of thing. We noticed a minor pricing problem on the SPAMfighter purchase page. Specifically, the US price is five dollars less than the Canadian dollar price even though the Canadian dollar is actually at par or slightly higher than the US buck as of this writing and for the previous few months. Obviously, SPAMfighter should leave it up to an ecommerce or transaction service provider to do conversions or simply set a single price and let the credit card issuers figure it out for cardholders who eventually end up paying in their local currency anyway. Money markets fluctuate far too much and far too often for software web site owners to keep up with monetary conversions. SPAMfighter needs access through certain operating system ports in order to share blacklist information and so on. If you're running a software firewall of almost any kind, you may have to manually configure a port. It's extra and unexpected work after installation but is also thankfully a relatively easy process. SPAMfighter has a comprehensive list of firewall configuration instructions here for every popular firewall on the market.

Pros: We love to see certain milestones which add confidence. Microsoft's partner program for independent software vendors remains one of the best ways for small software companies to ensure that their products are fully and completely tested and developed in compliance with Windows programming and development requirements. So the SPAMfighter and SPAMfighter Pro Microsoft Gold Certified Partner designation seems to be one of the reasons that SPAMfighter integrates so well into Windows Mail (in Windows Vista) and cooperates fully and seamlessly with every version of Outlook and Outlook Express we tried. SPAMfighter and SPAMfighter Pro reduced spam messages on heavily littered accounts by 95% or more according to our results, an impressive performance by any measure. SPAMfighter is free for all non-commercial use, but the full version is only $29.00. Recommended.