In the top left corner select "File" and then "Account Settings".Step 2
Select the e-mail account you wish to configure and click "Change"Step 3
Make sure your incoming and outgoing servers are correct. This should always be mail."your domain" (e.g. mail.i3d.net).
Your username is always your full e-mailadres.
Once you are done click "More Settings"Step 4
On the "Outgoing Server" tab of Internet Email Settings make sure the option "My outgoing server (SMTP) requires authentication" is turned on.Step 5
On the "Advanced" tab on Internet Email Settings set the Incoming server port to 993 and security type SSL/TLS. The outgoing server port must be set to 587 and security type to STARTTLS.
Once everything has been configured click OK and press Next. Your e-mail connection is now secure.
For additional port/connection information please take a look at this article
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