If the folder tree has focus, collapse either the currently selected branch or the optionally specified branch of the folder tree such that its children will no longer be displaying. If the item list has focus, Collapse all entries in a hierarchically displayed item list such that only the root entries are showing. This applies to lists viewed by discussion thread and tasklists that contain subtasks.
BFTKN_COLLAPSE_ALL or 1016
VOID CollapseAll(
[ANSISTRING] FolderName)
The full path of the folder tree whose children should be collapsed. Note that this parameter is ignored if the token is thrown a the item list.