Error when debugging a running Uniface app

Author: (lammersma)

Hi there,

I try to debug a running Uniface application with /deb=<processID>. All I see is a flash of a self-closing transcript window. In the transcript logfile I see:
UDBG(Error):  Can't open B-notify event  <  Het systeem kan het opgegeven bestand niet vinden.  >  ('Het systeem kan het opgegeven bestand niet vinden' is Dutch for 'The system can not find the specified file').

When I start de debugger without /deb, the debugger does start. Ofcourse without any connection to an Uniface process.

Can anyone point me in the right direction?

Kind regards


  1. Hi Peter,

    The Debug Thread is not started by default (when using Uniface 8.4.02 or higher), which means that it is not possible (without further ado) to hook the Debugger to a running Uniface application (udbg.exe /deb=pidID). The Debug Thread of the Uniface Runtime first has to be initialized (started) in one of the following ways:

    • use the command line switch /deb to start the Uniface runtime
    • execute the Proc statement debug in Proc
    • use the ASN setting $TRACE_IS_TRUE and start the debugger with the Gold key combination GOLD Y (Activate <Switch Keyboard> trigger)

    Hope this helps.

    Best regards,

    *** Usual disclaimer ***

    Author: diseli (
  2. Thanks, Daniel!

    Author: lammersma (