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Exchange Categorizer fails

jguderian asked
Medium Priority
Last Modified: 2012-08-14
I have an issue where an email from an external source seems to get caught in the Exchange Categorizer, and never gets delivered to the Exchange recipient. I have no idea where to look? I have checked the BadMail folder, but there is nothing there for this particular message, nothing in any queue, or the pickup folder. Where did it go?

So far I have only been notified about two instances from one sender, but we cant seem to recieve email from this person?

Any ideas?
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One more thing...

A "READ" reciept successfully delivered to the recipients mailbox form the send in question. So an email failed twice, but a "READ" reciept succeeded.

Just wanted to add that.
David WilhoitSenior Consultant, Exchange

did you find where in the cat it gets stuck? pre or post cat?

ikm7176Sr. IT Manager

Most of the time, if an outbound message is stuck in the categorizer it is
a problem with DNS. Make sure that you are ONLY pointing to internal DNS
servers in your TCPIP properties of the nic card. Also, take out any
references to other DNS servers from the Configure External DNS off the
Delivery Advanced of the Default SMTP Virtual Server. Then run ipconfig
/flushdns and ipconfig /registerdns

this link might be helpful



Kidego: How do I identify where in the cat it gets stuck? I just viewed the message in the "Message Tracking Center", which said the last step was the Categorizer. Is there somewhere else I can look?

ikm7176: This is not an outbound message. This email is from an external source. I appreciate your DNS suggestions, however I know that DNS is configured properly on the clients, as well as all servers.
David WilhoitSenior Consultant, Exchange

So you're able to find the message in the message tracking center, and when you clikc details, it just says the last place the message went was the categorizer? We need to turn up diagnostics logging on SMTP transport, probably to medium or maximum, whichever gets us the data we need to see.





I turned up the logging on both the Categorizer, and SMTP to medium.  I asked the sender of the original email to send me a response, so when I get that, I can give you whatever information you need.
David WilhoitSenior Consultant, Exchange

clear your logs and save them before you get too far, and you may want to increase the applog size. This will generate a TON of events....you sift thru them and watch the conversation.



Hmm... I have recieved sevearl email since elevating the log levels, yet there are no additional log entries? Does this require a reboot, or stopping of a service?

Withing Diagnostic Logging -> MSExchangeTransport is where I made my changes. Is this correct?


Just to throw a wrench in troubleshooting things. I happened to send a test email to the person who is getting stuck in the categorizer, and amazingly enough she replied, and I recieved it just fine. So here is the course of events

1. email@someplace.com emails internal Exchange recipient gets stuck in categorizer
2. "READ" reciept from email@someplace.com is successfully delivered to Exchange recipient
3. Additional email from email@someplace.com to Exchange recipient gets stuck in categorizer
4. I send email to email@someplace.com & successfully get a response

Why would the results of email coming from one specific sender to a specific recipient?

Again, the logging that I enabled isnt logging anything into the Application log.
Senior Consultant, Exchange
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