Configuring Anti-Spam RBL on Exchange 2010

If you use Google DNS as your DNS forwarders, RBLs don't work as Google returns "NXDOMAIN" rather than an RBL result.

1) Load the Exchange Management Console (EMC) and navigate to Organization Configuration > Hub Transport, then the Anti-Spam tab

2) Right click "IP Block List Provider" and choose Properties

3) Add the RBL you wish to use eg zen.spamhaus.org

4) Add multiple RBLs for extra filtering if required