GarageBand Plugins won't work because developer is not certified So I was downloading plugins for Garageband. They were Audio Units, so they work with Garageband, and I was also able to drag and drop my Component files into the Components folder, my usual process of being able to use plugins on Garageband. You know going to Macintosh HD&gt; Library&gt; Audio&gt; Plug-Ins&gt; Components. I've done this process lots of times. It works. But when I tried to use the new Plugins--Which I will say, do show up in Garageband--it says “Plugin Name.component” cannot be opened because the developer cannot be verified.&quot;. When I click Cancel it says &quot;Audio Unit plug-in can’t be used&quot; and then just does nothing.

This has been happening with all the new plug-ins I've been adding, I haven't been able to use one. I've tried restarting multiple times and it still says the same thing.
How can I fix this?
You could try removing the quarantine attribute, which likely causing the problem. See the answer here for details:
&quot;Install Spotify&quot; can&#39;t be opened because Apple cannot check it for malicious software