If your version of the Flash player plugin is either not updating to the latest version or working correctly, there is a tool available from Adobe to uninstall/remove the Flash player plugin here: http://kb.adobe.com/selfservice/viewContent.do?externalId=tn_14157
Once uninstalled/removed you can obtain the most recent version of the Flash player plugin here: http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash
This document applies to both Windows and Mac OS.