Setup Guides

Email, Microsoft 365, OneDrive, Teams and remote support

← Back to all guides

Mozilla Thunderbird

Thunderbird connects to Microsoft 365 over IMAP using a Microsoft sign-in.

You will need your Microsoft 365 email address, its password, and access to your MFA method (usually the Microsoft Authenticator app on your phone).
  1. Open Thunderbird, click the menu button (☰), then New → Existing Mail Account.
  2. Enter your name and Microsoft 365 email address. Leave the password field blank.
  3. Click Continue. Thunderbird detects Microsoft 365 and selects IMAP with OAuth2 authentication.
  4. Click Done. A Microsoft sign-in window opens.
  5. Enter your password, complete MFA, and accept the permissions request.
  6. Your mail folders will appear and begin syncing.
Thunderbird only handles mail. Calendar and contacts will not sync from Microsoft 365 without additional add-ons. If you rely on shared calendars, use Outlook.
Stuck on any step? Open a support ticket with support@diskman.net and we will walk you through it.