Microsoft has released Windows 11 on Arm ISO and I have some advice

Nearly six months after PC makers released the first Copilot+ PCs, Microsoft made Windows 11 on Arm available for download. But there are caveats. Aren’t there always?

If you’re familiar with this in the x64 versions of Windows 11, you know that there is a Download Windows 11 page on Microsoft.com that offers three ways to download and install the operating system. You can get a Windows 11 installation assistant, which is the longest but most reliable way to upgrade to the latest Windows 11 version. There is a Windows 11 Media Creation Tool that can be used to download the Windows 11 ISO (disk image file) and then optionally create installation media on a USB flash drive (or, amazingly, a DVD disc). And then there’s an instant ISO download.

But Microsoft has never offered anything like this for Windows 11 on Arm (or its predecessor, Windows 10 on Arm, for that matter). If you were lucky, your PC maker provided a downloadable recovery image, but to understand, most don’t. So if you had an unbootable or otherwise non-working PC, you had to consult your PC manufacturer’s support channels and hope for the best.

The other problem, of course, is that those who put Windows 11 on Arm PCs in the Windows Insider program may find themselves at the end of a one-way dead end street. The way this system is designed to work is that you can configure your PC to unsubscribe from whatever Windows Insider channel you’re using when that version of Windows 11 becomes stable. But because these channels aren’t always assigned to a specific version and usually don’t offer channel hopping, that milestone was never reached. So the only option was to reset this PC, try the cloud download option and, again, hope for the best.

What was always needed were the same options that Microsoft has always provided for Windows 11 (and earlier versions) on x64: a way to get the official, stable and current version of the operating system in a downloadable and installable form. At least an ISO.

And now Microsoft has finally done the least it should have done. Seven years after the first release of Windows 10 on Arm, three years after the first release of Windows 11 on Arm, and six months after the first release of Windows 11 on Arm version 24H2, it has given the world a single ISO download.

Hurrah.

But as mentioned, there are caveats. And I have some advice. Please pay attention to this.

First understand what is missing. For example, there is no Windows 11 on Arm Installation Assistant and no Windows 11 on Arm Media Creation Tool. All you can do is download the ISO file manually and then figure out how to turn that into a bootable USB flash drive yourself. I’m working on that now.

But whatever the need, this ISO should be the last option for anyone who owns a Windows 11 Arm-based Copilot+ PC. That is, you should make use of all the recovery and operating system installation options available on that PC for you even try to use that thing. You will need to create a recovery drive as I document in the Windows 11 Field Guide. You should try it Reset this PC. If you’re just trying to troubleshoot problems and not reset the entire PC, you can give it a try reinstall the new Windows with Windows Update functionality in 24H2.

But most importantly, if your PC manufacturer supports it, you should download the operating system recovery image for your PC and recreate (and then use) that recovery drive first. The problem is that not all PC manufacturers offer something like this, so you need to check. One PC maker that does offer this is Microsoft: You can download recovery images for Surface Pro 11 and Surface Laptop 7 from the Microsoft website. And you should too. You should ignore this new ISO download and use that one instead.

Why?

Because this new ISO download is lacking in two major ways.

First, it doesn’t include the 20-plus small language models (SLMs) that PC makers need to bundle on their Copilot+ PCs. For a clean install with this ISO, even if successful, you will need to manually download one or more SLMs each time you activate a Copilot+ PC feature.

That’s a minor inconvenience. But this one is more serious. As documented on the Microsoft Learn website“depending on the (PC) it will likely be necessary to include drivers from the device manufacturer in order to successfully boot the installation media.” Even worse, while Snapdragon X-based PCs shall If you boot using the drivers on the ISO, they won’t work properly until you install other drivers that aren’t included with the ISO. Such as network drivers needed to go online. This is how you get all the other drivers in the first place.

Here is Microsoft’s solution to this, which is familiar because I do this often with x64 PCs as well.

“(PCs) with a Snapdragon X Series processor will not have full functionality until the remaining drivers are installed. To install these drivers and restore functionality, use an Ethernet connection via a dongle or dock to connect to Windows Update to download the drivers. Once the drivers are installed and the device is restarted, all subsystems in the device will be functional.”

If you have an older Windows 11 on Arm PC, you’re on your own. In order for those PCs to even work with this ISO, the ISO must be updated with drivers from the PC manufacturers ‘injected’ into the image. Good luck with that.

There is one place where this ISO can be used without reservation: in virtual machines. This could be Hyper-V on Windows 11 on Armof course, but also Parallels on the Mac. If you’re using Parallels and Windows 11 on Arm is stuck at 22H2 or 23H2, you can use this ISO to upgrade it and take advantage of the performance benefits of the new Prism emulator. So at least that’s good news. The way I did this before, via a UUP dump downloadis not recommended for most people.

Anyway, we finally have the ISO. God help us all.