Flashplayer 20 installation not recognized

I use windows 7/ 64bit and Internet Explorer.  Having had problems with flashplayer, I uninstalled it using the uninstaller and procedure detailed in adobe help.  Flashplayer installer v20.0.0.286 downloaded and executed.  Installation completed (according to adobe) but flashplayer does not run (e.g. photobox.com says flashplayer not installed)