If you want to clear your DNS Cache in Windows 7, just click on the windows icon on the left bottom of your screen.
Once you click it, type ‘Command Prompt’ in Search Box. Then right click on the ‘Command Prompt’ and click ‘Run as Administrator’.
Then the black command prompt window will open. Then type ‘ipconfig/flushdns’ and press Enter. This will clear your DNS cache.
Then you will see the message as shown above “Successfully flushed the DNS Resolver Cache.”