I recently switched to Linux and need an Outlook alternative. My main personal Microsoft 365 account handles my email, calendar, and contacts, but I also manage several other email addresses over IMAP. I'd like one desktop client that can combine everything instead of using the Microsoft web app for one account and a separate client for the others. Evolution mostly works, but older messages in my Sent folder are incorrectly displayed as if they were sent today, which makes sorting and browsing difficult. What Linux email client would you recommend for reliable Microsoft 365 synchronization alongside multiple IMAP accounts?
3 Answers
Evolution is generally the closest Linux equivalent to Outlook because it supports mail, calendars, contacts, and Microsoft accounts in one application. The incorrect dates in Sent may be an Evolution or server-side quirk, though, so it may be worth checking the account configuration and comparing the same messages in the web interface.
Thunderbird’s Microsoft 365 support has improved considerably, but depending on the version and the features you need, Exchange support may require an add-on or a sufficiently recent release. It should still handle the additional IMAP accounts in the same unified interface.
Thunderbird is worth trying. Recent versions support Microsoft 365 through Microsoft Graph, and calendar and contact synchronization appear to work as well. Installing it through Flatpak connected successfully to a Microsoft 365 account without any special setup.

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