The OpenVPN project provides an installer for Windows 2000 through Windows 10, downloadable from The OpenVPN Community Downloads Page. At the time of this writing, the best version for most Windows users is 2.4.x-I60x installer. The 2.4 series is the most current stable release
The installation is straightforward, accept all the defaults. The installation will create a new Local Area Connection on the client system for the tun interface. This interface will appear connected when the VPN is established and will otherwise show as disconnected. No configuration of this interface is necessary as its configuration will be pulled from the OpenVPN server or client configuration.
On Windows Vista, 7, 8, 10 and later with UAC (User Account Control) enabled, the client must be run as Administrator. Right click the OpenVPN GUI icon and click Run as Administrator for it to work. It can connect without administrative rights, but it cannot add the route needed to direct traffic over the OpenVPN connection, leaving it unusable. The properties of the shortcut may be set to always launch the program as Administrator. This option is found on the Compatibility tab of the shortcut properties. One way around that requirement is to check OpenVPNManager before exporting to use an alternate OpenVPN management GUI on Windows.
The Viscosity client is also available for Windows and it does not require administrative privileges to run properly.