Thanks for the fast reply, appreciated. Just to confirm:

1) When you say "enable service" you mean to start it when system boots? I don't know if these services are already enabled and/or installed (sorry for my iognorance);

2) /etc/postfix/main.cf

Should I leave it as it is? The line with "content_filter = smtp-amavis:[127.0.0.1]:10024"

#
# Dovecot SASL support.
#
smtpd_sasl_type = dovecot
smtpd_sasl_path = private/dovecot-auth
virtual_transport = dovecot
dovecot_destination_recipient_limit = 1
content_filter = smtp-amavis:[127.0.0.1]:10024
smtp-amavis_destination_recipient_limit = 1
relay_recipient_maps =
smtpd_sasl_local_domain = here_goes_my_domain.com.br

3) /etc/postfix/master.cf

Should I comment out from "submission inet n" until "-o milter_macro_daemon_name=ORIGINATING"?

tlsproxy  unix  -       -       -       -       0       tlsproxy
#submission inet n       -       -       -       -       smtpd
#  -o syslog_name=postfix/submission
#  -o smtpd_tls_security_level=encrypt
#  -o smtpd_sasl_auth_enable=yes
#  -o smtpd_reject_unlisted_recipient=no
#  -o smtpd_client_restrictions=$mua_client_restrictions
#  -o smtpd_helo_restrictions=$mua_helo_restrictions
#  -o smtpd_sender_restrictions=$mua_sender_restrictions
#  -o smtpd_recipient_restrictions=
#  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
#  -o milter_macro_daemon_name=ORIGINATING
#smtps     inet  n       -       -       -       -       smtpd
#  -o syslog_name=postfix/smtps
#  -o smtpd_tls_wrappermode=yes
#  -o smtpd_sasl_auth_enable=yes
#  -o smtpd_reject_unlisted_recipient=no
#  -o smtpd_client_restrictions=$mua_client_restrictions
#  -o smtpd_helo_restrictions=$mua_helo_restrictions
#  -o smtpd_sender_restrictions=$mua_sender_restrictions
#  -o smtpd_recipient_restrictions=
#  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
#  -o milter_macro_daemon_name=ORIGINATING
#628       inet  n       -       -       -       -       qmqpd

Thanks!

OK, I've managed to make everything work back again with your help - Thanks. Actually, the only thing that was missing was the option ENABLED=1 (which was 0) in /etc/default/spamassassin

I am trying to manage SpamAssassin with Webmin, it it possible? If not, how can I setup whithelists/blacklists, and also  possible messages queued by SpamAssassin/Amavis?

Well, how it works, I don't know, but that's what made it work. [Edited] I don't mean to be disrespectful, please don't get wrong, ok? And sure, I may be wrong about it.

I am trying to manage SpamAssassin with Webmin, is it possible? If not, how can I setup whithelists/blacklists, and also   manage possible messages queued by SpamAssassin/Amavis?

Hi!
   Sorry for bringing this up again, but until today I couldn't make spamassassin to work. What am I missing? Do I have to install and activate procmail, too? Does it work when dovecot is using LDAP?
   Correct me if I am wrong, but if I use LDAP (Microsoft Active Directory), the web ui for iRedMail has no effect/use. If that is true, there is no point to buy a iRedMail-Pro license. I don't mean to be rude, it's a legitime question.
   Please, any help will be very much appreciated.

Thank you.