Library /sys$common/syshlp/dtm$dw_helplib.hlb mu, l_mu, l_cm  *Conan The Librarian (sorry for the slow response - running on an old VAX)

  Choose the Close menu item to close the active view
  window when more than one view window is open. This
  enables you to close the active window without leaving
  Digital Test Manager.

  You must choose this menu item from the active view
  window.

  This menu item is inactive if only one window is open.