Connecting to a mailbox

To do anything with an IMAP account you need to connect to it first. To do this you need to specify some required parameters:

• The server name or IP address of the mail server
• The port you wish to connect on

- IMAP is 143 or 993 (secure)
- POP is 110 or 995 (secure)
- SMTP is 25 or 465 (secure)
- NNTP is 119 or 563 (secure)

• Connection flags (see below)

Flag | Description | Options | Default | —— | —— | —— | —— |/service=service | Which service to use | imap, pop3, nntp, smtp | imap/user=user | remote user name for login on the server |/authuser=user | remote authentication user; if specified this is the user name whose password is used (e.g. administrator) |/anonymous | remote access as anonymous user |/debug | record protocol telemetry in application’s debug log | | disabled |/secure | do not transmit a plaintext password over the network | | |/norsh | do not use rsh or ssh to establish a preauthenticated IMAP session |/ssl | use the Secure Socket Layer to encrypt the session |/validate-cert | certificates from TLS/SSL server | | enabled |/novalidate-cert | do not validate certificates from TLS/SSL server, needed if server uses self-signed certificates. USE WITH CAUTION | | disabled |/tls | force use of start-TLS to encrypt the session, and reject connection to servers that do not support it/notls | do not do start-TLS to encrypt the session, even with servers that support it/readonly | request read-only mailbox open (IMAP only; ignored on NNTP, and an error with SMTP and POP3)

Your connection string will look something like this:

{imap.example.com:993/imap/tls/secure}

Please note that if any of the characters in your connection string is non-ASCII it must be encoded with utf7_encode($string).

To connect to the mailbox, we use the imap_open command which returns a resource value pointing to a stream:

<?php
$mailbox = imap_open("{imap.example.com:993/imap/tls/secure}", "username", "password");
if ($mailbox === false) {
    echo "Failed to connect to server";
}