After testing both tools for quite a while I decided to write down my impressions on their good and bad points.
Mozilla Thunderbird
Thunderbird delivers safe, fast, and easy emails, with intelligent spam filters, quick message search, and customizable views.
What I like:
*It's open source and free, is built by a community.
*Themes - allow you to change the look and feel of the user interface and personalize it to your tastes.
*Extensions - add on extra features without using shell hooks.
*Junk Mail filtering - Thunderbird uses Bayesian filtering which is one of the best forms.
*Cross platform - It runs natively on Windows, Linux and Mac OS X.
*Automatic folder compression - those DBX files can get awfully big, even if you delete all your mail. Thunderbird can compress them automatically, rather than waiting for you to do it yourself.
*On-screen alerts - You can have it pop up a message near the system tray when mail arrives.
What I did not like:
*Does not have an integrated calendar.
*Missing important rules - some very crucial ones, such as "Stop processing more rules" (very important) and "Display new email window".
*Flaky IMAP support - Thunderbird uses threading more efficiently and pretty much never locks up while retrieving IMAP folders. However, things get really strange when folders are created behind its back. Or deleted.
Summary:
Thunderbird takes the familiar look of Outlook Express and streamlines it, adding important, useful features without cutting back on anything. There's not a giant leap between this and Outlook Express.
Helpero rating 9/10
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