Open Source Alternatives to MailStore

An email archiving solution that allows users to retain, manage, and retrieve emails over the long term. The software provides capabilities for email compliance and eDiscovery, data loss prevention, and the reduction of email server load through de-duplication and compression. It is designed for home users, small to mid-sized businesses, and managed service providers. The product supports various email systems including Microsoft 365, Google Workspace, and IMAP or POP3 compatible servers. It can be deployed as an on-premises server or a cloud-native service. Users can browse their archive to recover emails and file attachments with a single click, while administrators can define rules for moving emails to the archive to maintain mailbox quotas. The system also allows for the central storage of PST files to remove the need for handling them on individual endpoints.

Whether you want to cut software costs or escape vendor lock-in, these open source alternatives to MailStore give you an option you fully own. You can self-host them, so your data stays on infrastructure you control. This page lists 2 open source alternatives to MailStore. The most popular are Mail-Archiver and Bichon. Most use the AGPL-3.0 or GPL-3.0 license, and 2 offer an official Docker image.