Step1. download OpenVPN
https://openvpn.net/index.php/download/community-downloads.html
Step2. install "TAP-Windows" only
Step3. Go TAP-Windows Folder
> cd C:\Program Files\TAP-Windows\bin
Step4. Edit deltapall.bat by Notepad, if need be.. like below (it needs to set write access)
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pause
"C:\Program Files\TAP-Windows\bin\tapinstall.exe" remove tap0901
pause
"C:\Program Files\TAP-Windows\bin\tapinstall.exe" remove tapoas
pause
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Step5. execute deltapall.bat