What Alex said is true, however, what exactly are you hinting at out here by asking that it does not work?
When you play Videos upstream, then the Flash works, cause many sites need compatability on your system to work those files. Site which generally have videos in any other format than FLV, MP4 & MPEG4, require these, at times even an AVI files requires this.
However, I will recommend you to keep uplifting your flash to the latest version, & always keep the last versions' .exe files within reach, so that you can switch to the older version, in case the latest crashes.