I managed to create new profile for firefox but when I try to play Non-HTML video (I tried both with and without del_prefetch.cmd) the error "adobe flash plugin has crashed" still appear and video is not loading. I am actually satisfied that after I performed the clean install flash player, at least now I can play Non-HTML5 video using internet explorer. I think maybe the root cause is from my Mozilla Firefox browser or my old laptop is not catching up with the new updates anymore (I think my laptop is more than 10 years old now since I bought it second hand 3 years ago). Thanks anyway for your kind assistance Carm01 and jeromiec83223024.