You can use IMAP to access your mail on Exchange, which allows you to continue using Thunderbird, or another non-Exchange mail client, even if your email is handled by an Exchange server. Using Exchange this way is not optimal, however, since only “full Exchange” use (e.g. with Outlook or OWA) will give you the complete range of features that Exchange offers, as outlined in the FAQ. However, many people have favorite IMAP clients that they don’t want to give up, or mobile device clients that can only use IMAP, and for those situations, the ability to use IMAP with Exchange is a nice option.

Great! How can I set it up?

You would set up a new IMAP mail client just as you normally would – add a new Account using the IMAP and SMTP settings below. If you are transitioning to Exchange from ACS ( but continuing use of your current IMAP client, the ACS settings will continue to work until you have a chance to modify them, by switching to the settings below.

What about meeting invitations and resource scheduling? What about using Distribution Lists?

If you primarily use IMAP, you will still want to set up Outlook (or use OWA or an Exchange-compatible mobile client) in order to accept and send meeting invitations and do resource scheduling.

In addition, some mailing lists (e.g. are created as Distribution Lists on Exchange and, so, will only work if you write to them while using an Exchange-configured mail client. If you get a bounce-back message from a known-good mailing list address, it probably means that you need to use Outlook (or use OWA or an Exchange-compatible mobile client) in order to send to that address.

Can I use a mix of IMAP and “full Exchange” depending on where I am?

Sure! For example, you might use Outlook while at BU or on your phone, Thunderbird via IMAP when you’re at home, and OWA when you are traveling. As described above, if you get a meeting invite while at home on Thunderbird, you would need to log in to OWA (or another Exchange-compliant client) in order to accept it.

I was migrated to Exchange from another server. Why can’t I see my folders?

Those who were migrated to Exchange from another mail server (e.g. ACS) might need to subscribe to their existing folders in order to see them in the IMAP client. In Thunderbird, for example, you would use File-Subscribe to Refresh the folder list and then select the folders you want to display.

Will I have to use the VPN to read my Exchange IMAP email from off campus?

No. Use of IMAP with the recommended settings – SSL (port 993) – means that you will not need to use the VPN.