When I run
"..\bin\tapinstall.exe" install "..\driver\OemWin2k.inf" tap0901
To add the tap driver, all I get back is a "failed" message with no details and the tap driver is not installed in Windows 7. The paths are correct and I tried specifying the absolute paths and it still didn't work. Running as an administrator also didn't fix the issue, however if I run the OpenVPN installer (latest version) and only select the tap driver, it is installed correctly.
I'm trying to make OpenVPN portable and the only thing standing in my way is installing the tap driver from a .bat file such as addtap.bat which comes from OpenVPN.