When installing an MSI installation containing a number of custom actions,
if the installer fails on the first custom action, during rollback, the
installer will display an error dialog complaining that it cannot find the
InstallState files for each custom action. And no wonder, since it hadn't
even begun executing the rest of them. is there any way, other than
providing a custom external UI for the MSI and filtering them out, to prevent
these dialogs from being displayed?