Sylpheed is an open-source free and easy to use email client. It is lightweight and build with full of features. It has intuitive user-interface, with high reliability. A powerful spam filter feature is also available in it. It controls the junk mails. Sylpheed supports the plug-ins.
Sylpheed uses IMAP, NNTP, POP3 and SMTP protocols. Multiple accounts will configure in sylpheed. It saves the users database in MH file format. Sylpheed supports Windows, Mac and Linux OS.