Download OpenVPN Windows Installer from OPENVPN.NET DOWNLOADS
Run the installer and click Ok or Yes if any Security Warnings appear.
Continue and write down the installation folder path.
Download the OPENVPN CONFIGURATION files.
Extract the files from the zip and copy ca.crt and all of the configuration files to the config folder found in the installation path from Step 3 (Usually C:\Program Files\OpenVPN\config or C:\Program Files (x86)\OpenVPN\config).
Windows 7 and Vista users will need to right click on the OpenVPN shortcut on the desktop and choose Properties and enable Run this program as an administrator.
Connect by right clicking the OpenVPN System Tray Icon, navigating to the server and choosing connect.
When you are prompted, enter your username and password.