Access under Firewall
Alternate usernames
You need to log in with your full FastMail.FM username, i.e username@your.domain. You must use the username you used to sign up your account, not any aliases or virtual aliases.
Because some software has difficulty with the @ symbol you can use any of these alternatives:
username@your.domain
username#your.domain
username/your.domain
username=your.domain
Firewall access
FastMail.FM has a special proxy system whereby you can access each service (POP, IMAP, SMTP, etc) through any port number. The server names are:
IMAP: imap.proxy.messagingengine.com
IMAP/SSL: imaps.proxy.messagingengine.com
IMAP (alt namespace): imapalt.proxy.messagingengine.com
IMAP/SSL (alt namespace): imapalts.proxy.messagingengine.com
POP: pop.proxy.messagingengine.com
POP/SSL: pops.proxy.messagingengine.com
SMTP: smtp.proxy.messagingengine.com
SMTP/SSL: smtps.proxy.messagingengine.com
LDAP: ldap.proxy.messagingengine.com
LDAP/SSL: ldaps.proxy.messagingengine.com
XMPP: chat.proxy.messagingengine.com
XMPP/SSL: chats.proxy.messagingengine.com
If you use these server names, you can use any port to access these services. Commonly open ports are 80, 21, 25 and 443.