If spam can automatically be sent to a folder by server-side processing, that is usually the best solution. This allows the site administrator to use the filtered spam email for training the Bayesian filter in SpamAssassin.
When this cannot be done, users can filter spam in the email clients they use. Most email clients provide some filtering ability to create folders and automatically move certain email messages into them. This filtering can be done either on the basis of headers that SpamAssassin adds to emails or on the basis of the contents of the Subject of the email. This chapter covered the configuration of filters in popular email clients, such as Microsoft Outlook, Microsoft Outlook Express, Mozilla Thunderbird, and Qualcomm Eudora.
