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As of macOS Catalina 10.15.4, the operating system has issued individual warning messages immediately after booting, indicating outdated system extensions that will no longer be supported in the future. The exact wording of the notification is as follows:
Legacy Extension - Software on your system loaded an extension signed by "Developer's Name" that will not be compatible with future versions of macOS. Contact the developer for assistance.
The first few times I ignored the hints, but they are slowly getting on my nerves and I wanted to get down to work to remove the system extensions or kernel extensions that will no longer be compatible from macOS 10.16 onwards.
The first thing that strikes me: the hint from the system, in which the outdated system extensions are pointed out, is almost completely for the feet. The name of the developer is mentioned, but the program to which the extension belongs cannot be found in the window.
There is also no indication of the path where the system extension can be found. So all that remains is to search for it yourself with the vague information.
My first glimmer of hope for the search was the CleanMyMac X tool, which I usually use to clear out startup items and the like. Unfortunately, it doesn't show the extensions macOS chalked up in any of the lists I clicked through.
Unfortunately, this means that a simple way via a Klickibunti program is apparently impossible and you have to look for other ways to find what you are looking for here.
A reader has just pointed out to me that the software "MacUpdater"in the new, purchased version 2 can also search for outdated software in the system and thus also find kernel extensions. I clicked on the software directly and it actually shows me four kext files that need an update. You just have to first select the setting "All software types" in the options under "Scan". This is not possible with the demo version.
After searching some forums, I came across a terminal command with which you can display the kernel extensions that are NOT from Apple. To do this, open the "Terminal" utility program and enter the following command:
mdfind 'kMDItemKind == "Kernel Extension"'
Update: A reader just wrote me that this command did not return anything to him. However, by entering this line he was able to generate a list of third-party KEXTs:
kextstat | grep -v com.apple
The Mac will then spit out a list of extensions that you should take a closer look at. The practical thing about this list is that you can see directly in which folders the files are located.
To make a list of the folders in which the KEXTs (abbreviation for Kernel Extensions) are located, I just looked in my results to see where they are. Here are the "usual suspects" I found on myself:
MacOS moves all kernel extensions into the "StagedExtensions" folder that wanted to install third-party programs, but this was prevented by the system for security reasons. Usually, after installing such extensions, the System Preferences> Security> General for a short time a note that allows you to authorize the installation. To do this, you have to enter the admin password and the kernel extension goes into the "Extensions" folder, in which it is then also executed.
If you don't miss anything at the moment, you can usually empty the "StagedExtensions" folder with the following terminal command:
sudo kextcache --clear-staging
Before you diligently push all kinds of files into the trash, you should familiarize yourself with Carbon Copy Cloner, Smart backup or SuperDuper make a 1: 1 backup with which you can also start again. When working in system folders, you can break a lot, so in the worst case, you won't even be able to boot your Mac from the volume.
It should also be noted that some manufacturers use extensions with multiple programs. So if you only use certain parts of Adobe CC or Microsoft Office, you usually still need all the system extensions that install the programs. If you remove this anyway, the software sometimes no longer works properly.
If you have any questions about the system extensions, please feel free to leave them here as a comment.
Jens has been running the blog since 2012. He appears as Sir Apfelot for his readers and helps them with problems of a technical nature. In his free time he drives electric unicycles, takes photos (preferably with his iPhone, of course), climbs around in the Hessian mountains or hikes with the family. His articles deal with Apple products, news from the world of drones or solutions for current bugs.