Office 365, Email, Exchange, Thunderbird

This page contains information about how to connect to the Exchange email and calendar service using Thunderbird.


Thunderbird is a free, open-source product and there isn't a vendor for us to escalate to. We will try to help troubleshoot but in the end you might need to visit forums for solutions. This article is correct as of 8/29/2019 to setup an account from scratch. It isn't intended for changing settings when people are migrated. Customers will need to remove their account from Thunderbird and follow the steps below.  

If you run into trouble and are faculty/staff you should speak with your local IT pro about using officially supported email clients.

Thunderbird is available for several operating systems from (external link).

After downloading and installing it, follow these directions to configure Thunderbird to get your email from the Exchange system. These directions will work for both the Mac and Windows Thunderbird clients.

Configure Thunderbird for Email

  1. In the Mail Account Setup window, enter:
    • Your name: Last name, First name (i.e., Smith, John)
    • Email address:
    • Password: Your AD password
    • Remember Password: (optional, your choice)
  2. Click Continue. Thunderbird will lookup your server information and default to the IMAP protocol.
  3. Click Done.
Thunderbird is now configured to connect to Exchange Online and should show the following:
  • The incoming address for Exchange Online (Office 365) mailboxes is: via STARTTLS on port 143 with Normal Password Authentication
  • The outgoing address for Exchange Online (Office 365) mailboxes is: via STARTTLS on port 587 with Normal Password Authentication
  • Username: 

  • Keywords:Exchange, email, calendar, Thunderbird, IMAP, SMTP, SMTP-Illinois, STARTTLS, Exchange, migrations, office 365   Doc ID:47659
    Owner:Office 3.Group:University of Illinois Technology Services
    Created:2015-02-26 12:10 CDTUpdated:2020-12-22 11:51 CDT
    Sites:University of Illinois Technology Services
    Feedback:  11   15