Use the File menu to expand or collapse all directories
  or to exit the Browser.

  Choose the Expand All option to open all directories
  on all levels at once. Use Expand All with care if you
  have a large namespace. The larger a namespace, the
  longer it takes to display its entire contents.

  Choose Collapse All to close an expanded namespace.

1  –  expand_all

  Choose the Expand All option from the File menu to
  expand (open) all directories on all levels at once.
  When you use this option, you see the contents of all
  of the directories to which you have read access.

  Object entries can represent nodes, clearinghouses or
  any resource for which a client application creates an
  entry in the namespace.

  Note: Use Expand All with care if you have a large
  namespace. The larger a namespace, the longer it takes
  to display its entire contents.

  For information about other ways to expand a single
  directory or selected groups of directories, see the
  Help topic, Displaying the Namespace.

2  –  collapse_all

  Choose Collapse All from the File menu to close an
  expanded namespace. You can also double click on the
  root directory to close an expanded directory.