Hi, After some tests, the good trigger name is loadError . But this trigger don't trap all http errors. I managed to trap some http errors  like error 105 (and only code no text ...)  but not 404 (like indicate in the documentation). I close this discussion (with myself !!!  ) and open a call. Thanks. Gilles.

Hi Gilles, Thanks for the info. At the moment I can only confirm your findings. This needs to be investigated in more details. So please open a new call for this. Thanks, Daniel Uniface Support   P.S. I've asked that the documentation is corrected (the trigger is called loadError and not onError)