Hello Antone,
If the user is running in reduced UI mode(/qr), adding an "Execute custom action" call to the Yes button in CancelDlg will cause the button to fail to close CancelDlg, fail to progress to UserExit, and cause the install in ProgressDlg to resume as if the user had pressed "No".
This is a strange behavior, indeed. I was able to reproduce this on our end, but unfortunately it reproduces sporadically. This is still under investigation on our end since we have not yet came to a conclusion on this.
Setting aside all of that, what I need is a way to bring up the UserExit Dialog when running in /qr. What controls which dialogs appear in /qr and which don't?
This is the default behavior of the Windows Installer technology. When running a setup with Reduced UI, only the modeless dialog boxes that have been authored into the UI will be displayed (e.g. Error Dialog boxes, Disk Prompt messages, FilesInUse Dialog boxes). I am afraid this behavior can not be changed.
Will come back to this thread as soon as I will have a conclusion on why the first issue occurs.
All the best,
Catalin