Can't send emails

When i try to send emails, got these error, no idea whats wrong.

This message was created automatically by mail delivery software.  A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:    xxxxx@gmail.com     host alt4.gmail-smtp-in.l.google.com [64.233.180.27]     retry timeout exceeded 

Reporting-MTA: dns; 13292-23641.bacloud.info  Action: failed Final-Recipient: rfc822;xxxxx@gmail.com Status: 5.0.0 Remote-MTA: dns; alt4.gmail-smtp-in.l.google.com 

nordic

Also noticed that Exim4 takes a long time to process incoming connections. I tried Postfix, it works just fast, but in the control panel the status of the mail server is immediately "not set"

perhaps the truth is in the file "exim4.conf.template" the field "rfc1413_query_timeout"