Allowing Avast Software extensions for Avast Security on macOS 10.13 (High Sierra)

The new macOS 10.13 (High Sierra) requires user approval before loading new, third-party kernel extensions. Avast Security for Mac uses kernel extensions for active real-time protection features. To ensure that Avast Security for Mac can fully protect your system, you need to manually allow Avast Software extensions.


To manually allow Avast Software extensions, follow these steps:

  1. Open Security & Privacy using one of the methods below:
    • If you use Avast Security 12.9 for Mac or higher, click Go to Settings in the Shields info dialog or on the main Avast user interface.
    ~ OR ~
    • Press the ⌘ command key and space bar simultaneously, begin typing Security, then select Security & Privacy.
  2. Ensure the General tab is selected.
  3. Click the Allow button next to System software from developer "AVAST Software a.s." was blocked from loading.
If the Allow button in your system preferences does not work, refer to the following video for instructions on how to allow Avast Software extensions:
  • Avast Security 12.9 for Mac or higher
  • Avast Security Pro 12.9 for Mac or higher
  • Apple macOS 10.13.x (High Sierra)

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