Have you just purchased a somewhat cheap USB WiFi adapter for your mac, only to find that the supplied driver fails to work. I was in that boat too.

I had downloaded and installed Wlan_11n_USB_MacOS10.8_Driver_UI_2.0.1.zip, which installs a utility application called ‘Wireless Network Utility.app’. Problem is, my machine is running El Capitan (10.11), so this driver seems a bit out of date.

The installed app never opened as advertised, and there was no new service in the list in System Preferences -> Network.

The fix? SIP – System Integrity Protection. El Capitan introduces this ‘feature’ which locks down your system in many ways, including preventing unsigned drivers from installing. You will want to turn this off.

To turn off System Integrity Protection:

• Restart your Mac
• Hold down Command + R while the Mac is booting to access the recovery system
• Open Terminal from the Utilities menu
• Type csrutil disable and press return
• Restart the Mac

Hopefully this post has helped you out a bit.