This option and the Load button are not needed if you have Entourage 11.2.3 or later and have Synchronize contacts with Address Book and .Mac checked in Entourage’s preferences.
If you have an older version of Entourage or if you do not wish to sync your Entourage contacts with the Mac OS X address book, you should:
With this option enabled, SpamSieve will not predict a message to be spam if its sender’s e-mail address is in the Entourage address book. However, if you have Exclude my addresses checked, addresses on the Mac OS X address book’s “Me” card will not be checked against Entourage’s address book. This helps prevent forged spams from getting through.
When you start using SpamSieve, you should click the Load button to make SpamSieve read in the addresses in the Entourage address book. (This will cause SpamSieve to launch Entourage if it is not already open.) The addresses are loaded into SpamSieve’s memory and stored in its preferences file, but they are not displayed in the Whitelist window because they are not whitelist rules.
If you have multiple Entourage identities, you can load the addresses into SpamSieve in sequence. Click Load, then change to another identity and click Load again, etc.
Whenever you add addresses to the Entourage address book, you should go back to SpamSieve’s preferences and click Load so that SpamSieve learns about the new addresses. If you remove addresses from the Entourage address book, you should hold down the Option key when clicking Load; this tells SpamSieve to forget the old addresses before loading the new ones. Do not click Load while Entourage is downloading and filtering mail, as this may cause it to freeze.
For more information, please see the How do I make SpamSieve catch spams sent from my own address? section.