Apparently AIG removed the post with the document in it.  Here is a Dropbox link.

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Couldn't figure out why I couldn't use a separate ai aircraft folder in FSX Sim Objects for use in making simple AI Flight Planner 3 ai plans.  Ernie pointed out that the FSX.cfg file must be edited to add the path to a new Sim Object folder. The AIFP3 manual is verbose and not geared to beginners making simple plans.  If there was reference to the FSX.cfg edit I missed it. I think this will end my frustration. Didn't want to dump all Ai Aircraft in the regular flyable aircraft folder.  Thanks