Since downloading Internet Exploer 8 anytime I click on a URL imbedded in a Word Document that ends in a PDF extension the system defaults to Intenet Explorer even though my default browser is clerly set as Firefox. This doesn't happen with any other imbedded URLs that don't have the PDF extension. Is this a Microsoft problem of an Adobe issue? Any known fixes? An hour and 1/2 on the phone with Mocrosoft provided only the normal frustration and no solution.