Microsoft Outlook is an email client available commercially as a standalone product or as part of Microsoft Office 2003. It contains the anti-spam capabilities you would expect in a commercial product, including
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Outlook does not include a native Bayesian analyzer, although it does have Junk E-Mail Filter with Microsoft SmartScreen Technology. In order to get Bayesian-style content filtering, one of the following packages can be used:
Microsoft Research has developed its patented Junk ...