POP3 and IMAP are the two most commonly used protocols for retrieving e-mails from an e-mail server.

Gustavus supports both protocols, but strongly recommends IMAP. In the summer of 2007, we made some improvements to our e-mail architecture, however these changes made an environment which is best suited for IMAP clients, and POP3 users could potentially experience minor glitches, like occasional duplicate messages.

What is the difference between POP and IMAP? When you check your e-mail with POP you ask the mail-server for your e-mail and it is delivered to your machine locally, and typically removed from the server. When you check your e-mail with IMAP you ask the mail-server for your e-mail and the mail-server shows you your mail and lets you read it delete it and manage it, but the mail you keep stays on the server.

Why is IMAP better? Most of our users at Gustavus are checking their e-mail from multiple machines in multiple locations, IMAP is the best solution for this. It allows users to manage email from multiple locations and platforms, all synchronized without problems. IMAP mailboxes are automatically backed up, allowing immediate e-mail recovery in the case of hardware failure.

Advantages of POP3 Advantages of IMAP
best when using one machine best when using multiple machines
configurable with older generation hand-helds newer technology - more flexibility
locally stored e-mail server stored e-mail
back-up dependent on end user back-up done at server level
e-mail available from one machine only e-mail available from any machine on Internet
perception of security