Be careful if you use Microsoft 365 and Thunderbird

While the Supernova version of Thunderbird is expected by the end of the first half of the year, the software continues its development under the aegis of Mozilla, with an important novelty for Microsoft 365 users.


Thunderbird version 127 features a significant change in how developers handle OAuth2 authorization for Microsoft 365 (formerly Office 365) accounts.

To meet Microsoft’s publisher verification requirements, Thunderbird developers had to apply the new Azure application and adopt the new application identifier. However, some of these accounts are configured to require administrators to approve any application that accesses email.

Now, an additional step is required for users who currently use Microsoft-hosted accounts, such as through their employer or educational institution.

If you encounter a screen that says “Need administrator approval” during the login process, please contact your IT administrators to approve Client ID 9e5f94bc-e8a4-4e73-b8be-63364c29d753 for Mozilla Thunderbird.

On January 19, an important communication was released: Thunderbird 102.7.0 should have been released on January 19, but the rollout was delayed due to a critical issue. A matter of days, according to the developers. The full and final version will eventually be 102.7.1.

Leave a Comment