1. Download Memcached on your computer
  2. Install Memcached service, then run it.
  3. Verify your PHP code is compiled with Memcached. If not, you’ll need to recompile or download a pre-compiled version of PHP.
  4. Load the memcached extension from within PHP, and restart your web server.
  5. Memcached should now be functioning.

See this URL for further details: https://pureform.wordpress.com/2008/01/10/installing-memcache-on-windows-for-php/