There is no app.path property - there is a doc.path property for a document, but not for the application. If you want the path for a document before it actually opens, you need to use a Acrobat plug-in.
You can run JavaScript when Acrobat starts by creating a folder level script. You put this script into one of two directories (either on the user or the system level), and then Acrobat will execute it whenever it starts.
Take a look at the SDK documentation for more information about folder level scripts. You can actually get the path to the JavaScript directories via the app.getPath() method.
Karl Heinz Kremer
PDF Acrobatics Without a Net
PDF Software Development, Training and More...
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