This is how i got it to work (OpenVPN GUI and Private Internet Access (PIA). No rebooting required:

uninstall all tap adapters in device manager>network adapters
install openvpn with default options
https://swupdate.openvpn.org/community/releases/openvpn-install-2.3.6-I603-x86_64.exe
add string value/data ComponentId/tap0901 (REG_SZ) with regedit
value name=ComponentId
value data=tap0901
to key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4d36e972-e325-11ce-bfc1-08002be10318}\[0001]
where [0001] stands for the instance on your system in which you find the REG_SZ string with
value name=ProductName
value data=TAP-Windows Adapter V9
disable and enable TAP-Windows Adapter V9 in device manager>network adapters to reinitialize the driver with the newly added ComponentId