Has anyone ran into this... 1. Create a Sales Order 2. Click Save 3. See this pop up... Click "Cancel" seemingly nothing happens. Pop Up goes away If the user clicks save again... - a new pop up displays stating... "You may have already submitted this form." Hours have gone bye and SO does not save to the DB.

Sounds like you have a script running in the background with a redirect on it. It's trying to redirect you before save.