If it is the corporate OU that you are wanting to omit have you tried:
*OU=Corporate* (star at the beginning was missing)
No there are no services. The exe runs on a scheduled task an has no services associated with it and all config is read new each time.
If the above doesn't work just put a * by itself. In theory this should just omit everything. Does that work? That tells you if the file is being read or not.