We were using SMTP to send emails to outside domains. Most of the time, the emails went through. But often we received a bounce message that said:
Action: delayed
Status: 4.4.7
Will-Retry-Until: Thu, 20 Feb 2014 13:45:16 -0700
To troubleshoot this, we tried:
Perform a telnet to port 25 on the remote domains mail server, it usually gives an indication of why you cannot send to them.
1. Go to start run, type cmd ok
2. nslookup -type=mx theirdomain.com
note the fqdn of their mail server
telnet fqdnoftheirmailserver 25 (hit enter)
mail from:you@yourdomain.com (hit enter)
rcpt to:them@theirdomain.com (hit enter)
data (hit enter)
. (hit enter)
. (hit enter)
Should say message was queued.