Library /sys$common/syshlp/dbg$help.hlb DEBUG, Messages, DISPRLENSIZ  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 the size of display_name is too small for its display-window
 increase the display size or decrease the display-window length

    Facility: DEBUG, VMS Debugger

    Explanation: You attempted to (re)size a display, e.g.
    DISPLAY/SIZE=n or EXPAND/DOWN=m, such that the defined display
    size is less than its display-window length. (See the SHOW
    DISPLAY command.) This is not allowed. The command was aborted.

    User Action: Try again with either a larger display size, e.g.
    bigger n in DISPLAY/SIZE=n, OR a smaller expansion, e.g. smaller
    m in EXPAND/DOWN=m.