Solved A costly lesson I just learned about W11 Upgrades

Per your item 1: you must have gone for an upgrade, rather than downloading an ISO.

I'm running 26100.1000 (24H2). I'm downloading a 23H2 ISO from Microsoft as I write this.

This is not to support Microsoft. Downloading an ISO should be a simple and obvious procedure, for people of all skill levels.

I don't recall seeing a list of the old graphics cards that you tried. "Old" covers a range. My first graphics card in 1995 was PCI (Not PCI-E). That was in my first, and last appliance PC (Dell). Later I had more advanced AGP cards. I don't recall what my first PCI-E card was.

Yes, I needed to do an upgrade rather than a clean install because I couldn't tolerate reinstalling all the user software on the system. I'd done that before a few times and I remembered that the ISO asks whether it should do an upgrade, keeping all user files and software, or a clean install that deletes everything and installs just Win11.

Birk said:

1. I knew I'd need the official MS Win11 upgrade install ISO, so I tried to download it on my PC which has been running Win11 for a long time. The MS downloader told me I was already running the latest version of WIn11 and would not do the download. So I got it using the Win10 system I was trying to upgrade to Win11.

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It looks like you were trying to do an upgrade instead of downloading the ISO. That would explain the message.

I had no problem downloading the current ISO from the official website from my laptop with Windows 11 Pro.

Download Windows 11

Birk said:

Yes, I needed to do an upgrade rather than a clean install because I couldn't tolerate reinstalling all the user software on the system. I'd done that before a few times and I remembered that the ISO asks whether it should do an upgrade, keeping all user files and software, or a clean install that deletes everything and installs just Win11.

Click to expand...

I'm not certain, but I believe that if you mount the ISO and launch an upgrade from it, you don't get a "clean" install, even if you don't choose to keep your existing files and programs. I presume that some OS-related files from the previous installation will be carried over.

If I want a clean install, I delete the partitions on the target drive, and start over from scratch.

As already said you can download the ISO directly from Microsoft site if you scroll down (third option). Running Setup from the ISO gives you the choice for a new installation (first option) or for upgrade (second option, advanced). So you can upgrade using the official ISO. While upgrading to Windows 11 and staying online, Windows Setup tried unsuccessfully to install drivers for your old graphics cards, hence your issues. If you were disconnected from the internet during the upgrade you would have avoided this since Setup would not be able to mess with drivers or other updates. Read my previous post.