How to Fix Extensions Blocked by Gatekeeper in macOS 10.13 High Sierra

In our recent post titled macOS 10.13 High Sierra Significantly Improves DisplayLink Performance & Stability we talked about how the latest update to macOS improved behavior when using a DisplayLink product (such as the Plugable UD-ULTCDL docking station). To go with that, we wanted to take a moment to discuss the Gatekeeper security feature introduced back in OS X 10.7 which has gone through some changes in High Sierra that may affect installation of some 3rd party device drivers used in devices from Plugable and other device manufacturers. For Plugable, the issue will only impact our products which don’t have drivers already built-in to macOS, such as our USB Docking Stations, USB Graphics Adapters, and USB Ethernet Adapters. Essentially this issue can affect any extensions not developed by Apple. Thankfully if you encounter this, there’s a simple process to fix. Keep reading for additional information and instructions.

In macOS 10.13 High Sierra, when installing new software and extensions, Gatekeeper now requires users to manually approve any new third-party extension before the computer can load and make use of the extension that was installed. This is important as many devices rely on extensions to function properly, and in some circumstances it can look like the software to power a device was installed but the device still doesn’t work. When this happens, users will see the below message:



If you suspect Gatekeeper is preventing an extension from loading, follow the below steps:

  1. Open System Preferences and navigate to the Security & Privacy section.
  2. In the General tab, look for a message at the bottom of the window stating “System software from developer DEVELOPER NAME was blocked from loading”, like in the screenshot below:

    For Plugable products, the developer listed in the message should be “DisplayLink Corp” for DisplayLink powered products (such as docking stations that do not use Thunderbolt 3 technology) and “WEI LU SU” for Plugable ethernet adapters that use ASIX chipsets (as of the time of writing this, all Plugable USB network adapters use ASIX chipsets).
  3. Click Allow, and from there macOS should now be able to properly load and use the extensions and software that were installed.
  4. Test things out! In some instances, you may need to restart the computer for the extension to properly load. So if it doesn’t work immediately, reboot the computer and the extension should load correctly.


Once an extension from a developer has been allowed, this makes the developer a ‘trusted’ source. Meaning that future extensions that are installed from the same developer should not be prevented by Gatekeeper from loading and should not need to have these steps repeated. However, software and extensions from other developers will encounter this same issue and you will need to follow these same steps.


For additional information on Gatekeeper and the behavior described in this post, check out the below Apple and DisplayLink support documents!

Feel free to share your experiences with High Sierra in the comments below, and if you’re having issues installing driver extensions for any of your Plugable products, please email and we’ll be happy to help!

macOS Compatibility

Unfortunately, due to changes in macOS 10.15 Catalina and support for third-party drivers, we are unable to continue support for macOS with our ASIX USB to Ethernet adapters (USB3-E1000, USBC-E1000, USB2-E1000, USB2-E100, USB2-OTGE100). Our USB3-HUB3ME and future USB to Ethernet adapters will use Realtek based chipsets that utilize drivers built into macOS.

OS X: About Gatekeeper

Technical Note TN2459: User Approved Kernel Extension Loading

macOS High Sierra: Video Functionality Not Enabled

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