Windows Upgrade Help and more

I’m trying to upgrade my Windows 10 PC to Windows 11, but the setup keeps failing with error code 0xC1900101. My main worry is my files. I did a full backup to an external drive using File History before starting, but I’ve heard some people still lose data. Is File History enough, or should I make a system image too? I don’t want to mess this up.

Quick tip: First, that error often points to a driver or software conflict. Run the Windows 11 Installation Assistant to check for compatibility issues before trying again.

Your File History backup is good for personal files, but for total safety, I'd also create a system image. It's a full snapshot of your current drive, so you can restore everything exactly as it is now.

You can make a system image by searching for "Backup and Restore (Windows 7)" in the Control Panel and following the prompts to save it to your external drive.

Once you have both backups, try the upgrade again. If it fails, you can restore from the image and your files will be perfectly safe.

+1 Another option is to run the Windows 11 Installation Assistant, as it sometimes handles the upgrade process more smoothly than the regular update tool.

You could also create a full system image backup for extra peace of mind, since that captures everything exactly as it is.

Can confirm. Another option is to run the Windows Update Troubleshooter first, as that specific error can sometimes be fixed by clearing update-related glitches. Hope that helps.

Just to be sure, did you also check if your PC meets all the Windows 11 requirements, like TPM 2.0 and Secure Boot?

You could also try using the Media Creation Tool to do a clean install instead, which sometimes bypasses upgrade errors. Another option is to double-check that your backup includes everything by browsing the external drive.

Following these steps fixed my issue as well.