hi shanti, i would recommend uninstallig the flash player first,a great program to help is 'revo uninstaller' its a free program that will remove basically all files and drivers associated with any program you wish to uninstall.just remember to check all the boxes regarding files to delete after the uninstall wizard has removed the program.
next i would go to the adobe flash site(link below).
then dissable your antivirus while you install the flash player.
after the adobe download manager has done the install,close your browser and reopen it again.
your flash player should now work.
http://www.revouninstaller.com/revo_uninstaller_free_download.htmlhttp://get.adobe.com/flashplayer/