What I'm most curious about, and what the docs are light on detail about: does this mean Thunderbird complies with remote deletion requests (which IIRC, the Exchange protocol suppports)? I have the impression that Microsoft makes this a requirement for Exchange implementations, which is why third-party devices and apps like Apple's Mail cooperate with those requests.

    Enable and disable Exchange ActiveSync for users

    Set policies such as minimum password length, device locking, and maximum failed password attempts

    Initiate a remote wipe to clear all data from a lost or stolen mobile phone

    Run a variety of reports for viewing or exporting into a variety of formats

    Control which types of mobile devices can synchronize with your organization through device access rules

While its been a long time since Ive used Thunderbird, I just wanted to take the time to publicly say thank you.

Many HNers probably wont (or cant) remember the world of desktop mail clients but basically during the height of MSFT dominance there was only one real mail client: Outlook. Which Microsoft was starting to monetize heavily, ignore UX, and keep it windows only (cant blame them for that).

Then Thunderbird arrived on the scene, an OSS mail client that beat the pants off of Outlook in features, spam detection, IMAP support and a bunch of other things.

And it was free.

And you could use it on any machine.

This was a huge moment for OSS.

We owe a lot of credit to Mozilla and Thunderbird for rescuing us from a closed source world.

Guess this means I can cancel all my OWL subscriptions.

Fantastic news! I've been hoping for Exchange support for a long while.

"Great news! This makes Thunderbird much more versatile for business use."

"Native Exchange support is a game-changer for Thunderbird users."

"Thrilled to see Thunderbird improving integration with Microsoft Exchange

Nice to see, but unfortunately it's not uncommon for orgs using Outlook/Office to disable Exchange client support and require use of the official clients. It's highly unlikely and maybe not even possible, but I'd like to see desktop and mobile mail clients implement some kind of workaround.

I generally like Thunderbird... but something is weird. What ever happened to Sync? It was around the corner for next release like two years ago. And I'm not complaining about Exchange support, but I am a bit sad that JMAP is nowhere to be found yet.

Is this good?

This is a genuine question. I am not sure whether this is good or not.

It seems to only extend existing options? Or is there some trade-off?

Awesome news, can't wait until they implement calendar support and I can get rid of Outlook once and for all.

Thanks!

I have a few Exchange inboxes and once MS forces the “New Outlook” design, without allowing the legacy option anymore, im gone!

As former Exchange admin/Office365, it's use EWS (Exchange Web Services) which is being removed in October 2026 for Office365. So for most, this is extremely time limited.