2.2.2.2.1.8 PidTagHierarchyChangeNumber Property

Type: PtypInteger32 ([MS-OXCDATA] section 2.11.1)

The PidTagHierarchyChangeNumber property ([MS-OXPROPS] section 2.721) specifies the number of subfolders in the folder. The value of this property monotonically increases every time a subfolder is added to or deleted from the folder.