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My company have two exchange 2010 servers( mail1 & mail2). Both have Client, HUB, and Mailbox roles installed on them with DAG configuration.

Now my two questions are:

1)After activating the Anti-spam feature on Hub Transport,I open the Sending Filtering & add some domain to the Blocked Senders. But sender from those blocked domain still can send e-mail to recipient in my company.

2)they all have 3 thing in common that appear in Exchange Queue Viewer

  • From Address is BLANK. shows as <> in Exchange Queue Viewer List item
  • Source IP of those emails is all the same and it's not valid
  • List item 95% say Undeliverable: in the Subject line

Help me to resolve! Thanks!

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Those sound like Out of Office messages being sent by the server. Open one of them up and look at the information on the General tab. If the subject is "Out of Office" then these are Out of Office messages being sent by the server on behalf of users who have their Out of Office option turned on.

So what's happening is this:

A user turns on their Out of Office. The user recieves a spam email from a spoofed sender address. The Exchange server attempts to send an Out of Office message to the spoofed sender address. The message sits in the queue until it expires.

My suggestion would be to turn off external Out of Office messages if they're not absolutely neccessary. If they are neccessarry then you're just going to have to live with it. Take note that allowing external Out of Office messages is one way for a spammer to validate internal email addresses.

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Hi Thanks! but there are not e-mails regarding out of office. All are spam messages.Any suggestion? And how about the first question? – e0594cn Feb 7 '11 at 12:50
I don't know about number 1. Regarding number 2: did you look at the info on the general tab of one of the messages? Does the subject read Out of Office? – joeqwerty Feb 7 '11 at 13:22
Not read out of office & how to turn off external out of office messages in exchange server for all user? Thanks! – e0594cn Feb 8 '11 at 1:46

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