Due to the complex requirements for routing, NAT, and firewall functions, the OpenVPN Access Server is only available for the Linux platform. This does not mean it is impossible to deploy it on for example a Windows-only environment, as virtualization can offer a solution there, but it does mean you need the OpenVPN Access Server program to be deployed on a Linux platform, whether that is a virtual appliance or a physical device. Currently we support a variety of cloud infrastructure providers, virtualization hypervisors, and of course physical devices.
On our VPN server overview page you can see the various deployment possibilities.
If you check the software packages page, you can find the exact Linux distributions and versions that we currently support for the OpenVPN Access Server product.