Updated May 20, 2020
Are you looking for an e-mail program that has a ton of features? One that has a calendar, task scheduler, and can handle multiple e-mail addresses? Then look no further than Mozilla Thunderbird.

You probably have heard of Mozilla's popular web browser Firefox, but did you know they also have a great e-mail program, Mozilla Thunderbird? And it has some fantastic features too.
When it comes to free e-mail programs, they usually lack the features that you would find in the corporate standard Microsoft Outlook. Even the e-mail program that comes with Windows 10, Mail, has a limited feature set.
But with Mozilla Thunderbird, you get all sorts of features right out of the box. It includes a calendar, address book, and a task scheduler.

Account settings inside of Mozilla Thunderbird
When it comes to e-mail, Mozilla Thunderbird can handle multiple e-mail addresses (POP or IMAP) and can send mail in either plain text or HTML format. You can also add signatures (HTML or plain text) for each e-mail account.
Mozilla Thunderbird includes an adaptive junk mail filter for each account; you have to train it using the Junk toolbar. You can also request return receipts, just like in Outlook.
There are also message filters similar to rules in Outlook so that you can automatically process mail as it comes in. You can create folder and sub-folders for local storage too.
When I compared Mozilla Thunderbird to Microsoft Outlook, I found they had almost the same features. Mozilla Thunderbird has a couple of features that Microsoft Outlook does not.
One of those features, just like Mozilla Firefox, is the ability to add more functionally with Add-ons. With Add-ons, you can extend what you can do with Mozilla Thunderbird.
Some Add-ons allow you to connect to a Gmail calendar, sync the address book with Gmail contacts, and create custom menus. And if you want to change the way Thunderbird looks, there are numerous themes too.
The only feature missing from the current version of Mozilla Thunderbird is the ability to import data from Microsoft Outlook. If you want to import Outlook data, you have to first install Thunderbird version 31.8, import your Outlook data, and then upgrade Thunderbird to the current version.
There are versions of Mozilla Thunderbird that run on Windows 7 through Windows 10, Mac OS X 10.9 through Mac OS 10.12, and GNU/Linux. For a complete list of system requirements, see the link below.
As with Mozilla Firefox, Thunderbird is also open source and free for personal/commercial use. Mozilla is a non-profit organization that relies on donations.
So, if you find Mozilla Thunderbird useful, donate to help support the ongoing development of it. Click here to go to their donation page.
For more information on Mozilla Thunderbird, follow the links below.
Mozilla Thunderbird
Mozilla Thunderbird - system requirements
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