Hi,
whether in Install or Maintenance sequence , I provide one more feature. User can update application using special attached files.
I've constructed custom action that reads a directory (always has same name, lets say FDIR) that can be attached to installation CD and this directory may contain special files that serve as update packages for my application. This update cannot be processed using AI, because some special actions are performed, that are not supported by AI (updating database, unpacking files etc... o are they supported?

). This action runs Updater that handles this actions.
So when installing or reparing, I need to send source dir (where to look for FDIR files) and destination dir (dir where app is installed). My custom action (console application) searches supplied source directory for those special files and runs Updater, that is always part if installation - in destination dir.
This feature is only available when there is FDIR. It might not be present in installation CD/package. To detect it's presence, I need to SEARCH for [SourceDir]FDIR Directory. And this is a problem during Maintenance.