Various experimental installers, drivers and packages are listed on this page. They may or may not be production quality.

OpenVPN 2.3.4 with NDIS 6 drivers (32-bit)	​openvpn-install-2.3.4-I602-i686.exe	​GPG signature
OpenVPN 2.3.4 with NDIS 6 drivers (64-bit)	​openvpn-install-2.3.4-I602-x86_64.exe	​GPG signature
Tap-windows6 (NDIS 6) driver installer	​tap-windows-9.21.0.exe	​GPG signature