IMAP

Create the Config File

nano ./username-muttrc

You should only need to change the username, password, and domain.tld entries to their respective values according to your user authentication information.

set my_mailproto="imap"
set my_mailuser="username"
set my_mailpass="password"
set my_maildomain="domain.tld"
set ssl_starttls = no
set ssl_force_tls = no
set spoolfile = "$my_mailproto://$my_mailuser:$my_mailpass@$my_maildomain/"
set folder = "$my_mailproto://$my_mailuser:$my_mailpass@$my_maildomain/"
set header_cache = /tmp/.username-hcache
set record = "Sent"
set postponed = "Drafts"
set mail_check = 60
set timeout = 10
set header_cache = "/tmp/.$my_mailuser-hcache"
set net_inc=5

Open the Mailbox

mutt -F ./username-muttrc

If the username and password are correct, you should be able to browse the mailbox from the terminal using your keyboard.