First, download and run the Flash uninstaller: [http://kb2.adobe.com/cps/141/tn_14157.html http://kb2.adobe.com/cps/141/tn_14157.html] . You probably want the 64-bit version. After that has run, restart your computer, and then let's download a fresh version of Flash. Try downloading and installing it from [http://fpdownload.macromedia.com/pub/flashplayer/current/licensing/win/install_flash_player_11_plugin_32bit.exe here]. Once you have flash installed again, start Firefox up, and see if you are getting any errors. If it works, awesome, if not, let's move on. Start Firefox up in [[Safe Mode|Safe Mode ]] (don't select any of the checkboxes that appear). If Flash works here, then it is one of your addons which is causing a problem. If we are still having a problem, try [[Updating your graphics driver|Updating your graphics driver]] . If none of these work, read [[Troubleshooting plugins|Troubleshooting plugins]] and let me know!