Question : How to configure exchange to use zen.spamhaus.org before message delivery

How can I configure exchange to use zen.spamhaus.org so we can reduce the amount of spam in the environment?

I think this is a 2 step process, but I am not sure.

Thanks!

Answer : How to configure exchange to use zen.spamhaus.org before message delivery

Assuming it is Exchange 2003 since you did not specify if it was exchange 2003 or exchange 2007.

I do not know if the zen.spamhaus.org needs any registration, but for configuring the blocklist follow the description on this link

http://www.msexchange.org/tutorials/Blacklist_Support_Exchange_2003.html

To activate the filter:
Then go to administrative groups -> first administrative group -> servers -> your mailserver -> protocols -> smtp

Right click Default smtp server.
On general tab press advanced
Choose your ip adress/ (all unassigned) and press edit
click Apply connection filtering

Then ok back to system manager.