Thunderbird and the EWS retirement

Microsoft Graph migration status from Thunderbird's own notices. Last checked 2026-10-15.

Thunderbird (Exchange accounts)

Status
Moved to Microsoft Graph
Date
2026-08-18
Vendor notice
https://wiki.mozilla.org/Thunderbird:Microsoft_Graph_API
“Microsoft Graph enabled for Microsoft 365”

Thunderbird Desktop 154.0 Release Notes (thunderbird.net) (2026-08-18), read 2026-10-15.

What to do. Thunderbird 154 (18 August 2026) adds Graph for Microsoft 365 mail; calendar is not supported on Graph yet. An account set up as EWS keeps calling EWS until it is added again as a Graph account, and a tenant admin must grant the new permissions in Entra.

Get an email when Thunderbird's status changes

One email from ewsappid.com each time a status on this page changes, nothing else, and none after 1 April 2027. Every alert has an unsubscribe link; one press deletes your address, or write to support@ewsappid.com at any time. Sender details are on the contact page; see the privacy policy.

Application IDs

Every app in your tenant

The tenant plan reads your EWS usage report in your browser and matches each app against these statuses and your current allow list. All vendor statuses.