Overview
Thunderbird is a free, open-source communication application. The desktop edition works on Windows, macOS and Linux. A mail client does not by itself replace a mail provider, an organization’s account policies or its calendar service.
What it is for
- Read and organize supported email accounts.
- Manage calendars and contacts with compatible services.
What to check first
- Check the organization’s authentication, calendar and account requirements.
- Back up local mail before changing storage or account settings.
A useful first test
Connect a test account and verify folders, sending, calendars and offline access before moving the main mailbox.
Cost and hosting
Free desktop application; mail hosting and optional services are separate.
Primary sources
This is a review of official documentation and source repositories, not a hands-on certification. Test your own files before migrating.