How to configure Exchange to properly reject emails to invalid users

07 Sep 2010

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	How to configure Exchange to properly reject emails to invalid users

Solution Exchange 5.5 :
Exchange 5.5 does not support rejecting invalid recipients at the SMTP transaction level. and is not supported by the Aussiecom Spam Blaster service.

Exchange 2000:
If you are using Exchange 2000, you should look at third party tools to reject invalid messages at the SMTP level.

Both GFI Mail Essentials and Vamsoft's ORF can filter on the active directory.

Exchange 2003:
Exchange 2003 introduced a new facility to filter email messages if the email address doesn't exist in the Active Directory. This will stop spammers from sending messages to non-valid addresses. The rejection is done at the SMTP level - so the email message isn't even delivered.

Enabling the option on Exchange 2003

1) Expand ESM, Message Delivery
2) Right click on "Message Delivery" and choose Properties.
3) Click on the tab "Recipient Filtering"
4) Enable the option "Filter Recipients who are not in the directory"

You then need to enable the Recipient Filter on the SMTP Server.

1) Still in ESM, Expand Admin Groups,, Server,, Protocals, SMTP
2) Right click on SMTP Virtual Server and choose properties
3) Click on "Advanced" next to the IP Address on the first tab
4) With the IP address selected, choose "Edit"
5) Enable "Apply Recipient Filter"
6) Click Apply/OK until clear

Information on Exchange 2007 coming soon

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Created On:

20 Aug 2008 06:07 PM