Kostenloses AntiSpam Programm?

Best Free Spam Filter for the Average
This is a difficult category as ordinary users need products that are easy to use and frankly, most free spam filters are way too complex to set up and use. The best products in this class are in fact, shareware not free. That said, MailWasher is for most folks, the best free option. MailWasher is an email preview utility that allows you to check your email on your mail server before you download it to your PC. The advantage of this approach is that you can kill unwanted messages including spam, viruses and large attachments before they get anywhere near your computer. MailWasher flags for you any messages containing possible spam and viruses for you to quickly check. It's a simple idea but quite effective and one which average users find easy to understand. The last free version of MailWasher [2] before it went commercial is still floating around the web. It lacks many of the advanced spam detection features of the current commercial version but is still quite effective. Alternatively, try XTerminator [3] which works much the same way as MailWasher and is totally free. I must say though, I prefer MailWasher's user interface.
[1] http://www.mailwasher.net
[2] http://www.321download.com/LastFreeware/page2.html#Mailwasher (1.57MB)
[3] http://www.artplus.hr/adapps/eng/xterminator.htm (1.87MB)
[4] http://www.techsupportalert.com/best-antispam.htm

Best Free Spam Filter for Experienced
There are many different spam filters available employing lots of different techniques. In my experience "learning" spam filters that use the Bayesian statistical approach out-perform most other types of filters I've tried. Not only are they better at detecting spam they are also less liable to classify your real mail as spam. This effectiveness takes a little time to develop as the filter has to be trained to recognize your spam from your normal mail. It takes a week or so before results start becoming accurate and best results may take a month or more. POPFile, a free, open source spam filter, was one of the first Bayesian filters and is still one of the best. It works as a proxy mail server so that means that it can be used with any POP email client. Setup is reasonably straightforward for experienced users but beginners may be better off with Mailwasher. If you use Outlook there are several excellent free Bayesian spam filters available including SpamBayes and K9. Both are simple to install though, like all statistical filters, they need to go through a training phase before they reach full effectiveness.
http://popfile.sourceforge.net/old_index.html (4.3MB)
http://spambayes.sourceforge.net/ (3.6MB)
http://www.keir.net/k9.html (113KB)

Vielleicht hilft Dir das weiter. Ich habe jedoch noch nichts getestet.