Thunderbird

Thunderbird is a full featured email program with built-in junk mail controls, message filters, address book, news groups and more. It offers a clean and easy to use (customizable) interface. Thunderbird also offers security features such as S/MIME, digital signing, message encryption, support for certificates and security devices. Other features include IMAP/POP compatibility, support for HTML mail, labels, quick search, return receipts, LDAP address completion, import tools and more.

Platform:
98/ME/2000/XP/Vista

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