INFO: WAB: Groups Are the Same as Distribution Lists (IDistList)

Outlook Express uses the Windows Address Book (WAB) to store contact data. The application used to view Address Book information (Wab.exe) refers to Groups, but the WAB application programming interface (API) makes no mention of Groups. In the WAB API, a Group is called a distribution list, and is represented by the IDistList interface.

Distribution lists can be distinguished from regular contacts by the value of the PR_OBJECT_TYPE property; the value for a contact is MAPI_MAILUSER, and the value for a distribution list is MAPI_DISTLIST.

When a distribution list is encountered, call the OpenEntry method to get an IDistList pointer. Because IDistList inherits from IMAPIContainer, the GetContentsTable method can be used on this pointer to get the contacts contained within the distribution list.

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