teseospa
I installed OpenVPN 2.2.2 one years ago on C:\OpenVPN [Windows 7].
On last friday I removed it and installed OpenVpn 2.3.1 on C:\Program Files\OpenVpn.
I started OpenVPN-GUI but it gave me an error.
I checked on regedit and I found on [HLM\Software\OpenVpn-GUI] all path with the old C:\OpenVPN.
I changed them manually and after all works perfectly.