If it is working for me - and it is(It even works on my android tablet) - means it is not a server config issue.
There are two versions of flash player.
One for Firefox and Webkit - Adobe Flash Player 11 Plugin
One for IE and Opera - Adobe Flash Player 11 ActiveX
Make sure you have the updated ActiveX plugin.
Or if you need to re-install:
Head to Control Panel -> Add/Remove Programs -> Uninstall Adobe Flash Player 11 ActiveX
And back to http://www.adobe.com/go/getflashplayer