Thunderbird 145 has been launched with full native assist for Microsoft Alternate electronic mail through the Alternate Net Providers (EWS) protocol.
Which means that Thunderbird customers in Microsoft Alternate environments (e.g., Microsoft 365, Workplace 365) now not want third-party add-ons and profit from seamless message synchronization and folder administration regionally and on the server.
Migrating from Outlook to Thunderbird can also be simpler, as Mozilla’s electronic mail consumer robotically detects the settings and makes use of Microsoft’s OAuth2 authorization protocol.
“Till now, Thunderbird customers in Alternate-hosted environments usually relied on IMAP/POP protocols or third-party extensions,” reads Thunderbird’s announcement.
“With full native Alternate assist for electronic mail, Thunderbird now works extra seamlessly in Alternate environments, together with full folder listings, message synchronization, folder administration each regionally and on the server, attachment dealing with, and extra.”
Thunderbird is a free, open-source electronic mail software developed by Mozilla, and Microsoft Alternate is an electronic mail and collaboration server broadly utilized by companies to deal with communications, calendars, and contacts.
Usually, organizations both use Outlook as the e-mail consumer app to hook up with an Alternate server or the Microsoft 365 cloud service. Nevertheless, any app with EWS assist, now together with Thunderbird, can hook up with it.
To maneuver from Outlook to Thunderbird, customers have so as to add the account in model 145 or later of the e-mail consumer, head to Account Hub > Alternate/Alternate Net Providers, and let the applying information them by means of the remainder of the method.

Supply: Mozilla
At present, the next options are supported:
- Alternate electronic mail setup and folder entry
- Viewing, sending, replying/forwarding, transferring/copying/deleting messages
- Attachments (save, show, detach/delete)
- Search (topic, physique) and fast filtering
- Microsoft 365 domains utilizing normal OAuth2
- On-premise Alternate with primary password authentication
The Thunderbird growth crew additionally plans so as to add assist for Calendar syncing, Tackle guide/contacts, Filter actions requiring full-message content material, Microsoft 365 domains requiring customized OAuth2 app/tenant IDs, On-premise NTLM and OAuth2 authentication, and Microsoft Graph integration.
No particular timelines had been offered for when these will land on Thunderbird, and implementation occasions could range per merchandise.
Mozilla notes that EWS remains to be extensively used, and Microsoft has promised to proceed supporting it “for the foreseeable future,” even because the tech large is transitioning to the Microsoft Graph interface as the principle technique to hook up with Microsoft 365 companies.
Whereas assist for the Microsoft Graph API is within the plans, the Thunderbird crew considers EWS a precedence proper now to fulfill the wants of a bigger person base.
Extra details about Thunderbird’s Alternate assist is out there on this wiki web page, whereas the assist portal supplies directions for account porting.
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