Flash 11.3 includes a new protected mode for Windows Vista and Windows 7, which seems to be causing issues for some users. You could temporarily disable this new feature to see whether it is creating the problem. In the following article, scroll down to the "Last Resort" section. [http://forums.adobe.com/thread/1018071 Adobe Forums: How do I troubleshoot Flash Player's protected mode for Firefox?] Please note that the Windows folder is a protected location, so you may need to save the configuration file to the desktop first and then drag it there.