It's probably the Application Modeler settings; depending on what you have, it could cause notepad to launch if it's not found for attaching.
In the Application Modeler Wizard, if you selected "My application is launched from an executable file", then you should be getting the same error as the tutorial. If you selected the "My application will already be running" option, you should get the same exception as the tutorial unless there is something in the "If not found for attaching" box, for example like this:
If you have something in that box, remove it, and you should be able to generate the same exception as the tutorial does. Hopefully that helps, but if not could you post your application modeler settings and a screenshot of your workflow?
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Nicholas Zejdlik
RPA Developer
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