How to Install Kernel Extensions in Mac OS X Manually
Advanced Mac OS X users may find it useful to know that KEXT (kernel extensions) can be manually installed. The process of installing kexts manually into OS X is not too difficult if you’re comfortable with the command line, but it is a multi-step process of copying the appropriate .kext file to the appropriate kernel extensions directory, and then using chmod and chown to assign appropriate permissions to the kext so that it will run as intended.
Manually Installing Kext into Mac OS X
You’ll need to use the Terminal to complete the kext install, this process is the same in all versions of OS X:
- Copy the .kext file(s) to /System/Library/Extensions/
- Open the Terminal and type:
- Type the following commands at the terminal, replacing the kext name with the one you are installing
- Now remove the kext caches:
- Reboot the Mac
sudo chmod -R 755 kextfile.kext
sudo chown -R root:wheel kextfile.kext
sudo rm -R Extensions.kextcache
sudo rm -R Extensions.mkext
The kernel extension should now be installed. You can query a list of the active kernel extensions in OS X with the kextstat command to be sure, use grep to limit the results.
Similarly, you can remove an item from the same /System/Library/Extensions/ folder to uninstall a kext file, rebooting the Mac again for the change to take effect.
As you can see this is more time consuming than relying on an app installer to place a kext itself, and it’s a bit more complex than the alternative like Kext Drop, so ideally you’ll just one of the installer applications instead, because most kext files are coming from an application installer anyway, right? Nonetheless, if you can’t use an installer app or a kext modifier app for some reason to install a kernel extension, the manual installation method outlined above works great in all versions of OS X.
Thanks to Nick for the tip