I apologize in advance if this seems like a post of previous questions. I believe I have exhausted every bit of the Google and Zimbra searches I can to find a solution to this.
I was running Zimbra Open Source Edition on Ubuntu 10.04. I was trying to install some unrelated packages that forced me into an upgrade of Ubuntu 12.04. The upgrade went smooth with no issues. I then downloaded Zimbra 8.0.5 to be compatible with Ubuntu 12.04 and proceeded to upgrade that. All went well, no errors during the installation. However, I am now unable to send email to anyone, anywhere. I have combed through the logs, and combed the internet and have yet to find a solution to my issue. The only error I can find is in the mailbox.log file and it is:
Caused by: com.zimbra.cs.mailbox.MailSender$SafeSendFailedExc eption: MESSAGE_NOT_DELIVERED; chained exception is:
com.zimbra.cs.mailclient.smtp.InvalidRecipientExce ption: RCPT failed: Invalid recipient firstname.lastname@example.org: 451 4.3.0 <email@example.com>: Temporary lookup failure
I have checked DNS and all is working correctly, that is what most of the answers I HAVE found pointed towards. I have checked mysql, and as best I can tell that works as well. Mail will not send to either internal or external domains, and it doesn't work with the Web Interface OR the Desktop Client.
Thanks in advance for any help, I will post answers and logs upon request.