Close Firefox
   Open the Windows run dialog
   Type %appdata% and run it
   Open the Mozilla folder
   Open the Firefox folder
   Open the profiles folder
   Open the folder with the .default at the end
   Rename the pluginreg.dat to pluginregbackup.dat
   Uninstall Adobe Flashplayer from your computer
   Reinstall Adobe Flashplayer from here 

I still have the same problem, I noticed there are 2 folders with .default at the end. I tried doing one folder, uninstalling and reinstalling, didn't work. I went back and did the other folder with .default and still flash is not being detected. I also made sure in add ons Flash is enabled to work. I'm at a lost now.

After following these instructions: Close Firefox Open the Windows run dialog Type %appdata% and run it Open the Mozilla folder Open the Firefox folder Open the profiles folder Open the folder with the .default at the end Rename the pluginreg.dat to pluginregbackup.dat Uninstall Adobe Flashplayer from your computer Reinstall Adobe Flashplayer from here I still have the same problem, I noticed there are 2 folders with .default at the end. I tried doing one folder, uninstalling and reinstalling, didn't work. I went back and did the other folder with .default and still flash is not being detected. I also made sure in add ons Flash is enabled to work. I'm at a lost now.