Using the mutt email client with Microsoft 365 Exchange Online

Posted on Friday, February 4, 2022 by TheBlackzone

More and more companies are outsourcing their email systems to cloud providers, most prominently to Microsoft 365 Exchange Online. Whether or not this trend is an improvement for the worse is up to discussion, but I recently found myself in such an environment and, since I prefer using the mutt email client for all of my emailing, I was looking how to connect it to my mail account.

So, getting straight to it, here are the necessary settings for IMAP and SMTP in the .muttrc configuration file to access a Microsoft 365 Exchange Online account (corporate tenant)…

IMAP configuration:

set ssl_verify_host=no set ssl_use_tlsv1_3=yes set imap_authenticators="login:digest-md5:cram-md5" set spoolfile={outlook.office365.com/ssl}INBOX set folder={outlook.office365.com/ssl} set imap_user="yourname@domain.tld" set imap_pass="yourpassword" set record="{outlook.office365.com/ssl}Sent Items" set postponed="{outlook.office365.com/ssl}Drafts" set mail_check=30 set timeout=60 

SMTP configuration:

set hidden_host=yes set smtp_authenticators = "login" set ssl_starttls = yes set ssl_force_tls = yes set from="yourname@domain.tld" set realname="Your Name" set smtp_url = "smtp://yourname@domain.tld@outlook.office365.com:587/" set smtp_pass="yourpassword" 

Tags: computer