Mozilla Thunderbird is a free, open source, cross-platform e-mail and news client developed by the Mozilla Foundation. Thunderbird can manage multiple e-mail, newsgroup and news feed accounts and supports multiple identities within accounts. It features quick search, saved search folders ("virtual folders"), advanced message filtering, message grouping, advanced spam filters, and labels to help manage and find messages.

Program Home Page: http://www.mozillamessaging.com/en-US/thunderbird/
Download: http://www.mozillamessaging.com/en-US/thunderbird/
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