Moving this discussion to the Installing Flash Player forum.
Do you use the 32-bit or 64-bit edition of Windows 7?
Download the appropriate installer from http://helpx.adobe.com/flash-player/kb/installation-problems-flash-player-windows.html#ins tall_in_a_firewall_proxy_server_environment and save it to disk, then close all browser windows and run the downloaded installer.
If you still have problems please specify what web browser you use. Also tell us what exactly is happening with Flash Player on your computer.