Windows 7 tells me that a 5.0 version of Adobe Acrobat, which came installed on your Dell Inspiron 5040 in November 2011, is incompatible with Windows 7. How do you correct this? If you have a previous version of Adobe flash player installed on your system, you must first uninstall that previous verison.
To do this you can go to an Adobe web page and download an uninstall program. Save that uninstall progam to your desktop and close all programs. Be sure to close all programs as well as that browser before running an uninstall program.
Once you have uninstalled that flash player, you can then install a newest version of Adobe flash player.