  Problems logging in? 
 The Question is:
 
Sirs,
     I am trying to upgrade vax4300 from vms v5.4 to v5.5. But after I
upgrade to v5.5 and finished. I found there are smoe messages :" error
modify opa0 " &amp; " system-i-illofunc illegal i/o function code ". And after I
type in user id &amp; password , it show
s "logged out ".
The problem is that I can't login system ,even if I login as system.
Please advise me how to figure out ?Thanks.
 
 
 The Answer is:
 
  When posting these messages, specific information on when these
  "error modify opa0" and "system-i-illofunc illegal i/o function code"
  messages are output would be useful -- without specific context, it is
  difficult to determine where in the startup or login processing these
  messages are arising.
 
  The OpenVMS Wizard would assume there are error(s) in the site-specific
  system startup or in the system-wide SYLOGIN.COM or in the user LOGIN.COM
  or in some constituent area of these procedures, or -- if CAPTIVE or
  RESTRICTED usernames are in use -- that there are problems accessing
  one of these or other procedures referenced by a CAPTIVE or RESTRICTED
  username.  (There may well be other causes, there is insufficient
  information here.)
 
  Also try adding the specification of the /NOCOMMAND qualifier on the
  username at the Username: prompt, to skip the execution of the LOGIN.COM.
  (Depending on the setting of the username flags and on the particular
  location of the error, this qualifier may or may not bypass the errant
  DCL code.)
 
  The console (OPA0:) has includes specific and deliberate checks that will
  permit access to OpenVMS in the event of certain severe errors.  There is
  not enough information here to determine if the problem is sufficiently
  severe that the console access path will be triggered here, but this is
  worth a test.
 
  Alternatively, try to bootstrap the system conversationally, and use the
  minimal startup option or the emergency login mechanism.  For details,
  at the website:
 
    http://www.openvms.digital.com:8000
 
  please see the following sections of the documentation:
 
    /72final/6017/6017pro_009.html#emerg_all
    /72final/6017/6017pro_009.html#control_start
 
 
