Editor: 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.
You can choose to download either the Minimalist ZIP file containing the K9 executable only (no installer or uninstaller) or the full installation EXE that will enable you to uninstall the application and all associated files and registry items if you wish to (recommended for first time users). When installing over a previous version you will not lose any information or "learning". K9 does not contain spyware, adware or any kind of malware whatsoever. 100% Pure. 100% free.
Expert Guide - Quick Start
How to configure K9
How to use K9
How to use K9's whitelist/blacklist feature
Advanced training techniques
Customizing K9's interface (partial alternate language support)
Frequently Asked Questions
Development History
The entire KeirNet website contents is available for download in the form of a Microsoft Compiled HTML (CHM) file. This file includes all of the documentation for K9 shown here and on the following pages. This may be a more convenient format for those who wish to read how to use K9 offline.
Please be aware that this file may not be available at all times due to excessive bandwidth usage!