You have to do those before trying to install a kext, or an app which installs a kext. With my external system up and running, the next step was to downgrade its security and enable the loading of third-party kernel extensions.

Sure enough, after reformatting the SSD and running the Installer again, with the SSD connected to a Thunderbolt port the first phase of installation completed successfully, following which came the sequence of black screens and white-on-black progress bars until the new system had to be personalised and configured. Connecting the SSD to one of the Thunderbolt ports is a much better bet. While you might be luckier than me, I wouldn’t bother trying to use one of the front USB-C ports, or one on the back of the Studio Display, for a bootable external disk. There had been no mention of any preparation taking place, and this was an initial installation not an update.Īccording to this notification, the external SSD had been disconnected without being properly ejected, which was news to me as it was still physically connected to the port. This error message is inevitably confused and confusing. The end of the first phase requires long waiting, in which the claimed “about 43 seconds” translates into ten minutes or more. Using the current Monterey 12.3.1 Installer app downloaded from the App Store with a freshly formatted SSD, I launched the installation process as normal, and selected the SSD as its target.Īs expected, this worked through the process of setting the owner of the new bootable system. Having discovered that SATA/USB-C SSDs are faster when connected to either of the front USB-C ports on a Mac Studio Max, that was my starting point. As I’ve lost count of the number of times that I’ve tried doing this over the past year and a bit, it’s now a well-worn path. The first step is to create an external bootable SSD, something I’ve already walked through, although I’m aware of many users who report that they can’t get it to work. So my plan was to build an external bootable SSD which runs at reduced security with SAT SMART installed, and to start up from that when I want to perform periodic checks on those SSDs. To do that on my Mac Studio, I’d have to reduce its security and allow the loading of third-party kernel extensions, something I’m not prepared to do with my production macOS. As several of those connect via USB-C, that means installing the SAT SMART kernel extension. One of my essential tools is DriveDx, which I use to check the health of my many external SSDs. I’m now in the middle of the long migration from my trusty iMac Pro to my flashy new Mac Studio Max, complete with its Studio Display.

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