VMS Help DCE_SECURITY, Admin Intro, DCE$IMPORT, SHOW, /EXCLUDE, Parameters  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 username

    Specifies the name of the OpenVMS account to be displayed
    from the IMPORT exclude list.  Full OpenVMS wildcarding is allowed.

    If /ALL is on the command line, do not specify a username.