The possible severity levels for diagnostic messages are as
    follows:

       S (success)
       I (informational)
       W (warning)
       E (error)
       F (fatal, or severe error)

    Success and informational messages inform you that the debugger
    has performed your request.

    Warning messages indicate that the debugger might have performed
    some, but not all, of your request and that you should verify the
    result.

    Error messages indicate that the debugger could not perform your
    request, but that the state of the debugging session was not
    changed. The only exceptions are if the message identifier was
    DBGERR or INTERR. These identifiers signify an internal debugger
    error, and you should submit a Software Performance Report (SPR)
    in such cases.

    Fatal messages indicate that the debugger could not perform your
    request and that the debugging session is in an indeterminate
    state from which you cannot recover reliably. Typically, the
    error ends the debugging session.