23H2 version of win 11 came out about a year ago. It would never install on my computer, even though my computer did pass the MS hardware health check. So I was stuck with Win 11 22H2.

I tried several ways every month or so, including from an ISO file. Finally today I figured out why 23H2 would not install: KB5027397 update must be on your computer or 23H2 will never install

Link to manually install KB5027397 from microsoft.com

https://catalog.sf.dl.delivery.mp.microsoft.com/filestreamingservice/files/caa3ff4a-6420-4341-aeae-33b2d7f463be/public/windows11.0-kb5027397-x64_3a9c368e239bb928c32a790cf1663338d2cad472.msu

After running that .msu, version 23H2 was installed automatically when I rebooted the system.

Here's where I learned how to do this (it's on microsoft.com):

https://answers.microsoft.com/en-us/windows/forum/all/how-to-get-and-install-kb5027397-feature-update-to/ad68e17a-ceb8-4076-85ba-3db7ff7a4f12

So if 23H2 won't install check Windows Settings for Windows update history and see if KB5027397 was installed in the past, or not.

if you install (properly, that is) from an ISO or from a USB flash drive it doesn't matter what you have installed as far as current Windows version or installed updates. just FYI.

9 minutes ago, molleh said:

if you install (properly, that is) from an ISO or from a USB flash drive it doesn't matter what you have installed as far as current Windows version or installed updates. just FYI.

Not sure your reference to "install" matches his reference.  You appear to refer to a fresh install. Apologize if I am wrong.  A couple of years ago I struggled to get a Windows annual feature update to install.  Took me 18 months of fighting off MS's failing attempts to successfully install that update. Do not recall now what solved the issue, but I followed a score of support threads from MS support sites without joy.   In the interim that was a blockade to other Windows updates such as security updates.  Was a totally frustrating experience, and the solution was not so simple.

I had same problem, for almost a year win 11 23H2 would not install. I had tried all the methods on the internet. But yesterday I installed KB5027397 but not through the Windows Settings Windows Update app because it was not shown there. I had to install KB5027397 manually using the installer only found directly on the Microsoft site (link above). That worked perfectly I assume because now for the first time Windows Settings / About shows 23H2 instead of 22H2.

What I did yesterday is google search "23H2 won't install" and landed on the Microsoft help forum where the MS support guy told the guy with the same problem as me to download the KB5027397 installer, run it, reboot the system and let the computer it do its thing, and then now check the version of Windows you have and it should be 23H3 instead of 23H2.

Anyway, I think similar problems and solutions are going to happen in about a month when 24H2 forces itself upon us all.

And now I have 24H2 installed. I used the MS Windows Installation Assistant (in case windows settings has not offered it to you yet, you can install it this MS approved way.

https://www.microsoft.com/en-us/software-download/windows11