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Are you on Sierra (OS X 10.12) or High Sierra (macOS 10.13)? There is a critical difference, and that was the introduction of a driver protection security in 10.13 which blocks the installation of drivers unless you explicitly grant them permission.
See this document for additional info.
If you missed that step, try downloading the drivers again, then run the uninstaller from within that package, reboot, run the installation then give the drivers permission in the system preferences.