Mozilla Thunderbird

                                                      
Thunderbird is a free email application
Thunderbird is an email, newsgroup, news feed and chat (XMPP, IRC, Twitter) client.
The vanilla version is not a personal information manager, although the Mozilla Lightning extension adds PIM functionality.
Additional features, if needed, are often available via other extensions.
With Thunderbird by Mozilla you can send e-mail, read e-mail and news fast, simple and free.
  (Review by (sajjadchanna.blogspot.com)