Email client keeps saying "Cannot find the server..."

[Spikerok]

Hello,

I have completed email set up on my server and have checked that email ports are open, but for some reason outlook keeps returning : "Outlook cannot find the server. Verify the server information is entered correctly in the Account Settings, and that you DNS settings in the Network pane of System Preferences are correct."

The odd thing is that outlook still picks up emails if I receive any, but keeps returning above error every minute.

 

[IgorG]

Check content of file /etc/host.conf File shouldn't be empty.
Also try to change configuration options that use 'localhost' to use '127.0.0.1':

# postconf smtpd_milters=inet:127.0.0.1:12768
# postconf non_smtpd_milters=inet:127.0.0.1:12768

and restart postfix service.