This error can occur for a number of reasons. The first thing you should do is to make sure that you are running OVPN as administrator. You can do this by right-clicking on the OpenVPN icon and choosing Run as administrator.
Open the Control Panel
Click Networks and Internet.
Click Network and Sharing Center.
Click Change settings for network adapter, which can be found in the left-hand column of the Control Panel.
Find the icon that says TAP-Windows Adapter V9.
Right-click the icon, and choose Change name. Change the name to tap0.
The network configurations are finished. Try to connect to OVPN again.