Hello Dear, the Error Code is showing the a Trojan or Malware have Replaced Some .dll installed Files inside the Firefox Installation folder in Program File, Just uninstall the Firefox using tool like Revo Uninstaller which shall clean the System Registry after uninstall is finish, then Reinstall Firefox, go to Settings and enable some Security Features including setting up your Mater Password and you will understand that MOZILLA FIREFOX IS THE SAFEST INTERNET BROWSER, Thanks, Google ZINCUBEC OMNI.