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Exchange outbound emails being delayed for almost 2 days to external recipients.

Posted on 2011-04-20
Medium Priority
Last Modified: 2012-05-11
As of a couple of days ago our Exchange 2007 server started delaying outbound emails to external recipients for about 2 days.

However, we can receive emails from external email address outside our LAN with no problems.

We can send emails within our LAN with no problems... inbound and outbound have no problems.

There are about 78 messages in the Exchange Queue Viewer Tool.

Question by:cmleavitt
  • 4
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LVL 125
ID: 35437210
are the external recipients mail servers down?

many external recipients, to the same domain?

I suspect that emails are leaving, because 78 emails doesn't sound alot?

Author Comment

ID: 35437224
I get this error mesage in the Queue Viewer:
451 4.4.0 Primary Target IP Address responded with :"421 4.2.1 unable to connect."

Emails are to various different domains.  It seems that they eventually go through... but like I said it seems to take a least 48 hours.
LVL 125
ID: 35437257
standard message, stating it cannot connect to the recipients mail server.

look at the emails, get the domains, find the mx record and mail server for the domain, and check it exists, and is available.

also check your DNS settings, that your server can resolve these mail servers, so ping from your SMTP mail server to mail servers you are trying to connect to.

We generally have hundreds sat there in the queue. (we don't worry about them unless theyy all start bouncing), email generally, will retry, and retry for delivery.

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Author Comment

ID: 35437353
There was new sonicwall firewall installed last week as well...

TZ 210 Wireless-N .... could this be causing the issue?

Author Comment

ID: 35437384
I am able to ping the reciepients email server from my smtp server with no problems.
LVL 125

Accepted Solution

Andrew Hancock (VMware vExpert / EE MVE^2) earned 1500 total points
ID: 35437441
check you can telnet <mail server ip address> 25

from your mail sever.

you should get an smtp message from their mail server.

if so, it may not have been available at the time. try retrying the queue.

Author Closing Comment

ID: 36019655
Partial Answer

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