K9 is an email filtering application that works in conjunction with your regular POP3 email program and automatically classifies incoming emails as spam (junk email) or non-spam without the need for maintaining dozens of rules or constant updates to be downloaded.

It uses intelligent statistical analysis that can result in extremely high accuracy over time.

K9 learns from its mistakes and becomes better and better at being able to identify spam. More importantly it learns to recognize what you consider to be spam.

K9 is for standard POP3 email accounts only. It does not directly support Hotmail, AOL or any other kind of webmail type systems, nor does it support SSL or secure authentication as used by MSN.

What's new in K9 1.28:

- Added support for customization of K9 resources (i.e. partial alternate language support). See Customizing K9
- Fixed a problem where if you kept the Escape key held down while attempting to open a message K9 would crash.
- Fixed a problem when canceling out of resetting statistics would reset the date/time shown at the column head.
- Added "View Folder" button to Statistics tab to open up a Windows Explorer window on the K9 database directory.
- Added date display to the email reader window.
- Modified system tray tooltip for Win9x systems since it seems those OS'es don't support line breaks in the text.
- Added/updated the following keyboard accelerator keys: CTRL-G = Good; CTRL-S = Spam; CTRL-B = Blacklist; CTRL-W = Whitelist; CTRL-1 = Recent Emails tab; CTRL-2 = Storage Area tab; CTRL-3 = Server Check tab; CTRL-4 = Configuration tab; CTRL-5 = Advanced tab; CTRL-6 = Statistics tab; CTRL-7 = Log tab; Enter = Read selected email; F1 = Help/Go to K9 website; F5 = Refresh; CTRL-O = Organize