Mozilla Thunderbird email client is a free open-source email client from the Mozilla Foundation. The same organization develops the popular Firefox web browser.
Thunderbird supports a wide variety of email services and protocols. Like Outlook and Live Mail, Thunderbird supports both POP3 and IMAP4 email protocols. In addition, Thunderbird automatic setup for several common online email services makes setting up internet email accounts a snap. For internet email servers without automatic setup routines pre-defined, Thunderbird attempts to automatically detect the email server's settings by trying common configurations and using standard email ports.
For example, when setting up an email account at my freelance writing business ArcticLlama.com, Thunderbird tried using mail.arcticllama.com as the incoming email name and smtp.arcticllama.com as the outgoing email server name. For those names it tried both POP3 settings and ports as well as IMAP settings and ports in an attempt to detect the correct settings. When it works, it makes setup and configuring Thunderbird email client server settings very simple. Of course, email server settings can be configured manually as well.
Unlike many other email clients, Thunderbird does not come with a built-in calendar. For users looking a pure email client, this is good. For users who would prefer an integrated calendar solution, Mozilla's calender and scheduling program, called Sunbird, integrates quickly into Thunderbird as user installed add-on called Lightning. Once installed, the calendar and appointment features familiar to Outlook and other calendar users are easy to access from within the Thunderbird email client.
Thunderbird offers many powerful email features including support for multiple email accounts, searching messages across all email accounts, and the option to view each email account individually, or as one combined inbox by using the "Global Inbox." Thunderbird offers several features to help organize a large volume of incoming email, including the ability to Tag and Star messages according to their category or importance.
Users looking for a free email client would be wise to start by looking at Thunderbird mail.