Cannot install Windows 11 - Error 0xc1900101

Yeah, I get you, I didn't want to roll back either. This year, finally, I began keeping good backups all year, so whenever there's a need to do a clean install, to fix an error, instead, I roll back to my last backup copy, which in the long run, ads even more stuff, since I'm never starting from scratch anymore, the software just keeps growing. Which makes it even harder to have to roll back to a clean install. But I already made a mistake by not making another backup since the Windows 11 install. when it was a fresh upgrade. I began playing with some apps last week that clean the registry. I always tell my customers to never use a registry cleaning app, because 9 times outta 10, it's going to screw your o/s up. you won't notice it right away, but within a week or so, weird things will start to show up. Like an app that has 3 or 4 individual compartments will lose a compartment from the app, or a startup app will just vanish from your "start with Windows" menu, or you launch an app, and the app throws up on the screen for a second or two then shuts back down and that's all it will do. And the shameful thing is I know better than to do it, but sometimes I just have to see if the app has made any progress over the years. Other times, it's necessary if you have to manually remove or uninstall a broken app that won't uninstall itself properly. It's either that, or spend the rest of the night manually going thru your registry, searching for that app's registry entrees manually, which is a total pain in the **** to do. So now I have a few quirks because of running a registry cleaner. Can't go back to a clean Windows 11, but I can go back to my last 10, then upgrade again to 11 I suppose. Again something I would rather not do. Perhaps if I do that, I may get the error again, but this time I'll try to pay more attention as to what I did to get past it, and if so, I'll be sure to drop in, and let you know what I did. Of course, that may or may not help your issue, since the code is very broad as to what it takes to fix, but it may help either you or someone else out. I may just do that tonight...All in the name of avoiding a clean install, it'll be worth it, to do it that way.

I also wish the update would stop keep trying to install. Every few days it tells me it needs to reboot to install, then fails and rolls back. I guess I could leave the Insider Program, but I wish they would fix this and push a good build, or at least respond to my feedback in the Feedback Hub about what this error means.

It sounds like you have a powerhouse box. My reference to naked is that I don’t want to go back there to be able to move forward with 11.

The error message really does no justice to us technically oriented people. It would be like having a brand new car that has one idiot light in it that says somethings wrong but I’m not gonna tell you.

Because of the enormous volume of files and the large library of applications, I am going to wait until some version past dot 65.

No, my machine is far from "A naked" machine...Asus motherboard Prime Z390 with a water-cooled 8700K CPU overclocked most of the time, near 5Ghz, sometimes higher, up to 5.2 so far (Need a bigger radiator) I have Dual video cards, an older GTX 650 TI Boost sitting in my 16x PCIe slot, and an Intel HD video card (embedded in the 8700K) 8 hard drives, 3 solo, 2 of the 3 are gum-stick m.2's and 4 mechanical drives of 1TB each, clustered in a raid 5 configuration, and 1 external 1TB USB drive. I'm running with two versions of Windows 10 (Now one is 11 and the other 10), Pro on C: and Home on D: (Home is for benchmarking scores only) dual booting into either/or, dual-monitors and tons and tons of software and games loaded on the machine along with a multi SD card reader, about 10 USB ports of all different versions, 3 HDMI ports and 2 display ports. 7.1 Surround sound system, (actually running as 5.1, at this time, but have two more speakers to add to it, I just haven't gotten around to that yet), RGB LEDs, and a DVD-ROM burner, and I no longer have an issue with Windows 11. That very evening when I wrote in this forum the first time about my error, I tried once more to get past the error I was getting, a second time. And It was installed without any hiccups, the second time thru. Enough said, case closed. Yeah so naked? No. Running Windows 11 Now? Yes. With very minor, mostly cosmetic bugs, and only two that I can think of. I'd say they've done a pretty jam-up job with 11 so far. And it's only going to get better from here. It's not much different from 10 however, under the hood, mainly it has gotten a face-lift and some menu rearrangements. Not many new options to speak of, although I hear it can run Android software now, I haven't tried that out yet. It appears to run with windows 10 drivers installed, so I doubt very seriously that drivers could be your problem if they weren't a problem in 10. I was thinking it could be that I was using a firmware version of the TPM chip, but no, that wasn't the problem either. So, frankly, I have no clue why it failed the first time. I made no changes, perhaps picked up a final Windows update before the 2nd install and it went fine, so go figure? Hope you figure out your issue, but I wouldn't rush to get to 11, like I said it's not much different than 10, other than a face-lift, and menu rearrangements. And they actually removed some features that I wish they hadn't. One, having the ability to make your taskbar icons smaller has been removed. And they removed the feature of being able to add a URL window on your taskbar. I miss those two features.

Rick

Do a complete windows reinstall and update!

Disclaimer: You will be losing all your personal files and data from the machine.

Follow this link to install windows.
You may click on this link as well: Download Windows 10 (microsoft.com)