Para instalar, o aplicativo deve ser executado no modo de compatibilidade do Vista.
Faça o download do OpenVPN 2.1 e, em seguida:
1) After downloading, right-click on the file and select 'properties' then 'compatibility mode'
2) Select 'Windows Vista (Service Pack 1)'
3) For privilege level, select 'Run this program as administrator'
4) Click 'Apply' and then 'OK' to exit
5) Double-click on the installation file install. Agree to any questions that pop up. Click next where prompted.
Note: The installation of the TAP adapter can sometimes take up to a minute. Do not exit the installer while the TAP adapter is being processed.
Quando o programa estiver instalado, você precisará marcar o OpenVPN-GUI no modo de compatibilidade com o Vista (SP1) e marcar a caixa de seleção "Executar como administrador".