I ran into the same problem, and here is what I have done to fix it. Go to Tools/Add-ons You might have to get the latest Adobe Acrobat Reader (Likely 10.x.....) On any exiting Adobe Acrobat Reader select disable (to disable the plug-in) If you have already gotten the latest Adobe Acrobat Reader just disable any earlier version. There is no official way to uninstall a plug-in so this it the workaround. If you do need to uninstall the plugin you need to type about:config ....about:plugins search for the article to do it.