VMS Help INITIALIZE, Qualifiers, /OVERRIDE  *Conan The Librarian (sorry for the slow response - running on an old VAX)

       /OVERRIDE=(option[,...])

    Requests the INITIALIZE command to ignore data on a magnetic tape
    volume that protects it from being overwritten. You can specify
    one or more of the following options:

    ACCESSIBILITY   (For magnetic tapes only.) If the installation
                    allows, this option overrides any character
                    in the Accessibility field of the volume. The
                    necessity of this option is defined by the
                    installation. That is, each installation has the
                    option of specifying a routine that the magnetic
                    tape file system will use to process this field.
                    By default, OpenVMS provides a routine that
                    checks this field in the following manner. If the
                    magnetic tape was created on a version of OpenVMS
                    that conforms to Version 3 of ANSI, this option
                    must be used to override any character other than
                    an ASCII space. If a protection is specified and
                    the magnetic tape conforms to an ANSI standard
                    that is higher than Version 3, this option must
                    be used to override any character other than an
                    ASCII 1. To use the ACCESSIBILITY option, you
                    must have the user privilege VOLPRO or be the
                    owner of the volume.

    EXPIRATION      (For magnetic tapes only.) Allows you to write to
                    a tape that has not yet reached its expiration
                    date. You may need to do this for magnetic
                    tapes that were created before VAX/VMS Version
                    4.0 on Digital operating systems using the D%
                    format in the volume Owner Identifier field. You
                    must have the user privilege VOLPRO to override
                    volume protection, or your UIC must match the UIC
                    written on the volume.

    OWNER_          Allows you to override the processing of the
    IDENTIFIER      Owner Identifier field of the volume label.

    If you specify only one option, you can omit the parentheses.

    To initialize a volume that was initialized previously with the
    /PROTECTION qualifier, your UIC must match the UIC written on the
    volume or you must have VOLPRO privilege.

    You can initialize a volume previously initialized with
    /PROTECTION if you have control access.