Mac software
Resolving riddles and restrictions with what you want to run on your Mac
Install an extension in Catalina
QI’m trying to use an app which needs to install an extension. This won’t work in Catalina, and the app complains the extension isn’t installed. What can I do?
AFirst check with the app’s support pages. Catalina is pernickety with extensions, and this varies with different extensions. When this works normally, running the app without the extension installed triggers installation. You’ll then need to agree to that in the General tab of the Security & Privacy pane, in what Apple calls User-Approved Kernel Extension Loading. This is only available for a short time.
Once approved, close the app, and you may need to restart your Mac. Restarts are normally required if your Mac has a T2 chip and runs with Secure Boot turned on. This is because the extension has to be built into those loaded with the kernel during startup. The only time this can happen is immediately before shutdown. It’s tricky, and you may need to repeat the process two or three times. Sometimes the only way to get the extension to load properly in a Mac with a T2 chip is to turn off Secure Boot. Restart in macOS Recovery mode and select Startup Security Utility from its Utilities menu. Authenticate as an admin user and select the lowest of the three options in the upper section, for No Security. When you’ve restarted in normal mode, installing the extension should then be straightforward. You may need to keep Secure Boot disabled to use the extension: check with product support.