Claws Mail is an open source email client. Claws Mail also includes Built-in anti-spam enables the scanning of incoming mail received from a different account using "Spam Assassin". It can delete mail identified as spam. It has graceful and very simple user interface so that any user can use it easily.
Claws Mail provides inbuilt anti-phishing security, Search and filtering features. Claws mail stores mails in MH file format and in MBOX file format via plug-in. It supports POP3, SMTP, IMAP and NNTP protocols. It is available for Linux, Windows and Mac OS.