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Blocking outgoing e-mails to a certain domain

Medium Priority
Last Modified: 2012-05-06
Is there any way of blocking outgoing e-mails to a certain domain from an internal network through Exchange 2007 or any other means.

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Sorry I forgot to say this is for Exchange 2007

you can restrict delivery on individual users mailboxes but it has to be from someone in the GAL

We only have a domain not an e-mail address etc


I have logged on to the Exchange 2007 Edge Server and gone to

Sender Filtering - Enabled this
Added the blocked sender domain.

This has stopped the domain being able to send to any users internally but I still need to know how to stop people posisibly sending to this domain from internally.
alter the smtp connector settings and add it there.


Could you give me some advice on how to do this.
Thanks :-)


If I create a new transport rule in Organisation Configuration/Hub Transport/Transport Rules/New Transport Rule, it does not allow me to do quite what we want to do.

It relies on the GAL for all the rules, there are no options for saying that from anyone internal trying to send an e-mail to xyz.co.uk, block message or send bounce message etc

You could create a DL and block anyone in that DL access to sending mail amongst other things but there seems to be no way to block all our users from sending out to one particular domain....
Expert of the Quarter 2009
Expert of the Year 2009
Transport rules can do this for you.
Simply activate the option "where a message header contains specific words" and enter the domain name. You may need to have multiple rules to catch all variants.

An Edge server can actually block on the recipient domain, but that doesn't seem to be available on a hub transport rule.


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