All the following instructions will require authentication, i.e., a login name and a password.

For your main Linux account, the login name for IMAP, POP, and SMTP will just be the Linux username (without appending any domain or other string to it). If you create additional mail accounts from within the Virtualmin control panel, then the login name will be as given to you by the control panel.

If asked what type of login, pick a normal or password login (but not encrypted password).

In each table given below, we have listed rows ranked in order of preference. For best security, use the highest preference row (lowest number) that works for you. In other words, the 1st preference row is the most secure, then 2nd, then 3rd; and the 4th preference row is the least secure.

Note that some software uses the terms SSL, SSL/TLS, or TLS/SSL to refer to TLS. So most of the time you are actually using TLS (more secure) when the software says SSL (less secure). The software authors don't want to confuse you by using correct terminology.

Only very old software actually uses SSL. Our server will accept some but not all variants of SSL. Just go down the table and use the first one that works for you. (Preferably not the 4th row.)

Note. To access Classic Linux legacy mailboxes, prefix a 3 digit to each IMAP and POP port. SMTP remains unchanged.

Automatically discovered parameters. Your mail client will usually try to discover suitable login parameters automatically, by trying common hostnames and ports derived from your email address. If it succeeds, please inspect the automatically discovered parameters and make sure they are reasonably secure. If your mail client automatically discovers parameters lower down in one of the below tables, it may be worth your while to manually try something higher in the table and thus more secure.

IMAP is more efficient than POP. 1st preference is most secure, 4th preference is least secure. IMAP is also known as IMAP4. To access Classic Linux legacy mailboxes, prefix 3 to each port; thus 993 becomes 3993 and 143 becomes 3143.

POP is less efficient than IMAP. 1st preference is most secure, 4th preference is least secure. POP is also known as POP3. To access Classic Linux legacy mailboxes, prefix 3 to each port; thus 995 becomes 3995 and 110 becomes 3110.

1st preference is most secure, 4th preference is least secure. To access Classic Linux legacy mailboxes, use the same port numbers shown below (no change).