Failed to send emails to any domain

[john.fernandes]

Hey guys!
I have a serious problem sending emails. I have already checked logs and other forums, but I can not find a solution. My email is stopped a few days ago. Out of nowhere he stopped sending. I can receive emails normally. Any help will be valuable. Thank you!

Ubuntu 14.04.2 LTS
Zimbra 8.6.0

[Raun]

make sure your IP is not blacklisted . It is the most common cause of the problem you described.

[john.fernandes]

No, I checked that out. My server is email.guarapari.es.gov.br