Not sure this will work, but

download and run this program to uninstall any version of flash which you may already have:

http://download.macromedia.com/pub/flashplayer/current/uninstall_flash_player.exe

restart the computer after this completes.

then goto http://www.adobe.com/shockwave/download/download.cgi?P1_Prod_Version=ShockwaveFlash

to install the newest version of flash.  I would deselect the option to install the yahoo toolbar, but that's really up to you.

good luck!