Unable to manage email


My Webmin/Virtualmin GPL is running into Debian 9 Stretch

I need some help by start to use email service in Wemin.

I have a clean OS and a clean Virtualmin installation.

Im able to use ftp and web server yet, im able to use SSL throught Let’s Encrypt too. This can be probed at my tld: https://domain.com

I did copy the Let’s Encrypt cert to Postfix and Dovecot and restarted all system

Now, i can not to use email, im unable to send/receive email from usermin or any mail client like Thunderbird. In fact, i can’t start session in Thunderbird, when i try to start session with my email account soporte@domain.com I get this error: “Thunderbird failed to find the settings for your email account.”

When I send email from usermin i got email dameon advise

I can’t receive email from usermin.

I hope some usefull help. Thanks