Configuring Mozilla Thunderbird for IMAP Over TLS/SSL

After configuring Thunderbird for a IMAP connection, these instructions may be followed to set up a secure connection using TLS/SSL encryption. This ensures all communications between the email client and our email servers, including user names and passwords, are protected as they are transmitted over the internet.

The server name should be changed to the appropriate abihosting.com hostname. In this case it should be imap.abihosting.com. Changing the server name will avoid name mismatch warnings when checking for email. This is due to the fact that the certificate used is for a specific name. This step is not neccessary; if you don't mind these warnings simply leave this field as is.

Under "Security Settings" choose the "TLS" radio button and uncheck "Use secure authentication". Using "TLS" rather than "SSL" causes the communication to take place over the standard IMAP port of 110; this is preferred to using the differnt port used by "SSL", as that may not work correctly with certain firewall configurations.

The options under "Server Settings" are mostly left up to personal taste. Leave "Check for new messages every _ minutes" at 5 or more. Checking more often than this may cause excessive load on the mail server. Doing so could lead to loss of service.

When connecting to the server over an SSL-encrypted session for the first time, a warning like in the image above may be displayed. The mail server uses a certificate signed by our own private CA (Certificate Authority). This does not lessen security in any way. However, the mail client will correctly warn you that it can not properly identify the cert. This is not a problem, and if you want to avoid these warnings in the future choose "Accept this certificate permanently" and click the "OK" button.

Thunderbird is now configured to communicate with the mail server using SSL encryption.