Hi DTS Engineer, I bought a cheap wired USB controller at Walmart, a TurtleBeach one. It apparently lacks Mac support, and when I tried to add it in Game Controllers system prefs, that only supports Bluetooth controllers in macOS 15.7. So I decided to write my own driver for this controller so I can use it. Took me a couple of hours to write the driver and an app to install it. But now i've been spending about 3.5 million years to try to get the driver to actually install. No matter what I do, I get the error: System extension request failed: domain=OSSystemExtensionErrorDomain code=4 Extension not found in App bundle. Unable to find any matched extension with identifier: (my identifier) Yet when I look in the app bundle: ControllerDriver.dext is present exactly in Contents/Library/SystemExtensions/ControllerDriver.dext ControllerDriver.dext has an embedded, signed provisioning profile with MYTEAMID.com.X.WiredUSBController.driver The driver has this entitlements file: ` The app has the entitlements file: ` I tried disabling SIP and ensuring that I set "sudo systemextensionsctl developer on" -- to no avail. I do have a paid developer account. Surely the system is not restricting me from writing my own driver for my own controller on my own computer for my own personal use, I must have something wrong in these settings. What is it? BTW, I did try your advice and attempt redoing this with the USBHost framework, but it fails to even auto-generate an entitlements file because apparently for this one you HAVE to get Apple's approval first. So I applied for it, but shouldn't I at least be able to get the prior attempt working? And do I really need Apple's approval just to write a driver to use my own hardware locally on my own computer?