Actually I download the flash player using internet explorer, as I watched in the video clean install flash player, the guy also download it using internet explorer. I tried to search for flash player in about:plugins but it was not listed there. I also tried to search in firefox add-ons for shockwave flash but it also not listed in add-ons (I tried to search for shockwave flash add-ons but no exact result found). Then I tried to play Non-HTML5 video in internet explorer and it works! So I did the clean uninstall again and this time reinstall flash player by downloading installer using mozilla firefox. After installation complete, I tried to play Non-HTML5 video in firefox but the error adobe flash plugin crashed appeared again. And this time I am also not able to play Non-HTML5 video in internet explorer anymore. So I performed clean install of flash player again by downloading installer using internet explorer and now I am able to play Non-HTML5 video on internet explorer only. Does it mean there is conflict between flash player installer and my firefox browser then?