Exchange server delay delivery to all out of organization emails

Hi

Did it work before?

Test the server connectivity from outside.

https://testconnectivity.microsoft.com/

Run inbound tests first. Post results.

Verify MX records.

http://mxtoolbox.com/

yes it has been working for years.  Seemed to stop at 6PM last night

Hi again,

Ok great, there can be some issues, first that comes to mind, is this server multihomed? One NIC goes to the internal network and second NIC connects to internet?

If so, does the server have a working internet connection?
If so? what is there to see in the event logs close to when it stopped working?

Last for this post, were there around this time updates installed? Windows updates, AV or malwaretools updates?

Inbound test failed:

Results:
Testing inbound SMTP mail flow for domain 'xxxxxxxxxxxxxxxxxx.com'.

The Microsoft Connectivity Analyzer failed to test inbound SMTP mail flow.

Additional Details

Test Steps

Yes we can get to the internet on that server.
We did see an critical event log where the server rebooted but that was much later in the night after the issue began.
Last updates looks like 12/16/2013 and it has been restarted several times since then

The users are receiving NDR messages?

I would do some tests as below:
 1. run exbpa on the exchange server, confirm whether there are some useful information
 2. use get-rereceiveconnector and post them here, we could check and do more research about your issue
 3. use telnet to connect your exchange server from internet, cnfirm it is ok, if there is some information, please post it here


Can you confirm that the Connectors has the anonymous permissions selected.

Could you temporarily disable AV and other malwaretools and firewall to check connectivity?

Wouldnt be the first time we see an AV update block communication for Exchange.

I ran the MX tool check it is doesn't look like we are blacklisted

Did you try to restart the microsoft Exchange transport service and check again if the problem conitnues?

Yes the users are receiving NDR messages

I will attempt to run the tests suggested

we are restarting the transport service right now

We think it might be the barracuda.  checking that right now

does anyone know how I can bypass the barracuda because we have verified that it is the barracuda.

Do you have your own appliance or use a barracuda supplier?

We have our own Baraccuda 300.  I don't know anything about this other than it's IP address.  I was not here when it was installed

I was not able to bypass the barracuda but I think it may be because I do not have the right IP address.   I will post results a little later.

Thank you all for your help.

Patricker1972 - you are awesome....Thank you !

Youre welcome, glad i can help.

Thanks again for everyone's help. We are getting a replacement barracuda because it was a total hardware failure. I had to redirect the email to and from the router as you suggested but the router had some rules on it that I didn't understand so I got some outside help to accomplish the router changes.   I will assign points tomorrow. But thanks again for the help

This solution worked for me