If you have already installed a Sonnet Driver and it is not loading:
1) Restart (forces Mac OS to scan for unloaded drivers).
2) Go to System Preferences...Security & Privacy panel...General tab. You will see a message, "System software from developer "Sonnet Technologies" was blocked from loading." Click Allow. Note that you must have a hard-wired mouse/trackpad to click allow. If you are connecting via Remote Access, then macOS prevents you from clicking Allow.
3) Restart.