Data type: PtypMultipleString ([MS-OXCDATA] section 2.11.1)
The PidTagAddressBookRoomContainers property ([MS-OXPROPS] section 2.560) contains a list of DNs (1) representing the address book containers that hold Resource objects, such as conference rooms and equipment. Messaging clients use this list to determine which containers have mainly Resource objects so that they can perform special actions on these containers, such as displaying a different column set when browsing address lists that are represented by these containers, or using features that require selecting from a set of rooms or equipment.
The DNs (1) in the PidTagAddressBookRoomContainers property each use the x500-dn format specification, as specified in section 220.127.116.11, with the additional requirement that there is no container-rdn in its x500-dn and that the RDN (2) of the object-rdn follows the container-guid format specification. When the RDN (2) is extracted from the DN (1), it represents the GUID of the address book container that this is referencing. Messaging clients compare this GUID to the GUID of another address book container by extracting that GUID from the container-guid of the other container's DN (1), which follows the addresslist-dn format specification. If the GUIDs are the same, the other address book container is a room container.