Sylpheed

Sylpheed is an e-mail client thought to create a complete connectivity experience through a simple yet reliable interface. As GNU software, this app integrates quite a big number of features. A 3-panned display embeds a comfortable reading area, an easy to configure working space and a powerful backup utility that won’t let you lose any mail.

Periodic compaction is nonetheless needed and may be considered a drawback. Several filters are also available when extra protection is required.

Junk mail control and support for almost all languages add to some important security features, such as message encryption. External commands may improve your working times a lot.