hi,

In the SMTP receive we can see an incoming message:
,250 2.1.0 Sender OK,
, RCPT TO:<*********>,
,250 2.1.5 Recipient OK,
,DATA,
,354 Start mail input; end with <CRLF>.<CRLF>,
,250 2.6.0 ********* Queued mail for delivery,
,QUIT,
,221 2.0.0 Service closing transmission channel,

- The message is not visible in mailtracker.

- the message is visible in the smtpreceive log and according to the logs everything is fine.

- We have no blacklist in our exchange server 2007.

- the e-mail address of the sender is not blacklisted.

- we use forefront, it's not visible in forefront.

- there is no virusscanner on our exchange server.

Where is the e-mail message? It seems like it's stuck somewhere, but we cannot find out where.

• Edited by Luitzen Tuesday, July 28, 2015 2:31 PM
• Moved by Jason Johnston [MSFT]Microsoft employee Tuesday, July 28, 2015 2:56 PM Not a development question.

Hi,

I suggest to try the following things:

1. Check the firewall.
2. Turn off SMTP traffic or any mail scanner.
3. Disable any Antispam software temporarily.
4. Increased the 'Connectioninactivitytimeout' value on 'Receive Connector'
5. Under Administrative Tools, Services, right click Microsoft Exchange Transport, and click Restart

And whats the NDR on sender side?

Best Regards.

Hi,

- There is no firewall.

- there is no mail scanner.

- the mail is not blocked by exchange forefront (the e-mail is not visible in forefront).

- transport service restart doesnt fix the issue.

- there is no NDR, because the mail is queued for delivery by the exchange server(according to smtp logs).

- I can't ask the sender the try it by telnetting, it's not possible due to circumstances.

any more thoughts?

Hi

When you say the message is visible in the smtpreceive log and according to the logs everything is fine then there is nothing that exchange is doing to block the emails

Did you check in the message tracking logs on all the  servers ?

I quote myself:

"- The message is not visible in mailtracker."

so yeah, it can't be found in the tracking logs (I also searched them manually).

Then there might be any transport agents blocking this message. I dont see any other things that can block this.

Can you check your forefront logs

According to the forefront logs it's processed and accepted, last part of logging:

,1,FSE Content Filter Agent,OnEndOfData,AcceptMessage,,SCL,-1

Hello 

can you use the below command to check the email messages using shell. 

Get-TransportServer -Identity "ExchangeServer" | Get-MessageTrackingLog -Sender ABC@mydomain.com -Recipients DEF@yourdomain.com -ResultSize Unlimited -Start "01/01/2015 12:00:00 AM" -End "02/13/2015 11:59:00 PM" | Export-Csv c:\temp\EmailTrace.csv

Let me kniw if you got some trace here.

I can but I won't, because checking the mailtrack logs from shell is totally pointless, since it's the same logging as the message tracking GUI.

This topic can be closed:

- Exchange management console -> organization configuration -> Hub Transport -> Anti-Spam -> disable Sender ID.

This solved the issue for now, the mail is now delivered to the mailbox. What is very annoying though, is that this is not logged anywhere. Troubleshooting Exchange issues is a nightmare.

• Proposed as answer by Sathish VeerapandianMVP 20 hours 30 minutes ago
• Marked as answer by Luitzen 16 minutes ago

Yes my guess was right that some transport agents will cause this issue on the categorization part especially for this sender

Though i wasn't able to drill down till the one which caused this trouble you found  the root cause

Thanks for s