Because Flash Player is a free product, there is no phone support for it. Using Safari, I will assume you're on a Mac.
Download the offline installer here: http://fpdownload.macromedia.com/get/flashplayer/current/licensing/mac /install_flash_player_11_osx.dmg
Quit Safari (don't just close the window - Cmd+Q to quit it altogether)
Mount the DMG and run the installer
If it won't run, go to: Mac HD/Library/Internet Plugins
Trash the Flash Player.plugin file from there
Go to: Mac HD/Library/Application Support/Adobe
Trash the Flash Player folder (the whole folder)
Empty the trash
Mount the DMG and run the installer again.