Thunderbird

As the top dog among email clients, Thunderbird [7] can now look back on some 18 years of development. Originally developed by the Mozilla Foundation, the program now resides under the umbrella of MZLA Technologies Corporation, a subsidiary of the Mozilla Foundation.

Thunderbird not only offers a mail client, but also the complete feature set of a PIM with a newsreader, a chat and messaging client, calendar and appointments management, and contacts. The package can thus be used as a communications center, removing the need for numerous individual tools.

Thunderbird can be found in the package sources of almost all distributions but can also be obtained directly from the project's website. Many distributions also preinstall the application as standard software for email management.

Wizard

Thunderbird opens a wizard to help configure an email account when it is first launched. Next to it, the program displays an information page in the main window that contains links to several wizards for setting up the different communication services supported by Thunderbird (Figure 13).

Figure 13: Thunderbird offers a matching wizard for each service.

After entering the email address, the wizard for creating the first email account automatically determines the access data from a Mozilla database for incoming and outgoing mail. The application supports IMAP and POP3 accounts and sets the port numbers and encryption methods accordingly. If the routine does not find an entry in the database for the provider used, you can enter the required details manually.

After saving the configuration, the main window of the application opens with several conventionally arranged segments. A vertical bar on the left edge of the window shows the folder tree for the individual accounts. Top right is a list of incoming messages, including the subject, sender, and date. The area below is for displaying the message. Above this are a few buttons for quick access to the most important functions; a menubar is missing.

Thunderbird, like most popular web browsers, supports a tab structure. Clicking on the icons for the calendar and tasks in the top right corner opens a new tab in each case. The hamburger menu located to the right of the search field gives you access to the configuration dialogs for the general Preferences , as well as the Account Settings .

The Preferences dialog primarily comprises of the general settings relevant for other modules, as well. Under Account Settings , you can tweak the email accounts by setting up end-to-end encryption with OpenPGP and S/MIME or configuring junk filters.

The software comes with its own spam filter, which does not require any additional configuration. However, it needs some time to learn how to distinguish useful messages from spam from the headers. In addition to this filter, you can also integrate external filters by placing a check mark in front of the Trust junk mail headers set by option in the Junk Settings configuration dialog and selecting the desired external filter in the selection field beside it (Figure 14).

Figure 14: Thunderbird embeds spam filters both internally and from external sources.

Thunderbird already supports numerous third-party spam filters by default. You can apply them to local folders, too, by checking the corresponding box in the dialog for this category. In both dialogs, you also specify the folder to which Thunderbird will move messages marked as spam.

To enable end-to-end encryption, configure your keys and certificates in the End-To-End Encryption option. You can use OpenPGP to generate keys or import existing ones. Note that you should continue to use existing keys, because any newly generated keys will no longer support access to older messages. You can also use external keys, such as those stored on a smartcard, with GnuPG.

Thunderbird also cooperates with externally installed antivirus solutions, if required, by letting them check incoming messages for malware and moving them to a quarantine folder, without storing them in the Inbox. This function is primarily recommended for POP3 accounts.

Trojitá

The Qt-based email program Trojitá [8] primarily targets less powerful hardware and users who only need an email client with a basic feature set. The software is only capable of handling a single IMAP account. The program can be found in the software archives of almost all distributions.