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Installing a new operating system is tedious enough of an experience. But run into major issues during the process, and it can become downright infuriating.
We’re here to help. Due to the nature of Windows installation problems, we can’t offer a specific procedure to fix every situation. Instead, we’ll look at several tips to try when Windows doesn’t install correctly, then cover some of the most common error messages.
1. Remove Unnecessary External Devices
This simple step is something you should try right away. If Windows won’t install properly, disconnect any hardware attached to your computer that you don’t need for the setup.
You can keep the mouse, keyboard, and monitors plugged in, of course. But remove headphones, USB drives, game controllers, phones, and similar peripherals. You can reconnect them later once everything is working.
2. Optimize Your Current Installation
If you’re trying to install a fresh copy of Windows over an existing installation, some problems on your current system might cause it to hang during the process.
Make sure you have a good amount of free disk space. 32-bit Windows 10 requires 16GB, and the 64-bit flavor needs at least 32GB. Install a tool like TreeSize that lets you see what programs and files are taking up the most space on your system and create some space.
Run all pending Windows updates on your current installation. Microsoft may have patched your issue in an update you haven’t applied yet.
Also, disable all antivirus programs and firewalls. If you’re performing an installation through Windows, security tools may interfere. Make sure you’ve restarted your PC recently as well, to clear up any temporary bugs.
Finally, on Windows 10, try the Windows Update troubleshooter at Settings > Update & Security > Troubleshoot > Windows Update. There’s no guarantee that this will fix anything, but it’s worth a try.
While we focus on installation in this guide, see how to fix Windows upgrade issues if you’re having trouble updating an existing system.
3. Check for Install Media Issues
The Windows 10 media creation tool makes it easy to install Windows 10 on pretty much any computer. However, you can run into a number of problems while using it.
It’s possible that the installer files became corrupted during creation. If this is the case, you’ll need to start fresh and create a new installer, since fixing it isn’t really possible. Follow our instructions to create Windows 10 install media anew and try again.
If you try it again with a fresh installer and it still doesn’t work, you likely have a hardware issue. Try another USB drive, or a different disc, if you have one. It’s also possible that you have a faulty DVD drive or USB port.
4. Fix File Corruption
It’s possible that a corrupted file on your existing system is preventing the installation from working. To scan and repair these, right-click on the Start Button and choose Windows PowerShell (Admin) or Command Prompt (Admin). Then run the following command:
DISM.exe /Online /Cleanup-image /Restorehealth
After this completes, enter a secondary command to run the system file checker:
Try your installation again once this is done.
5. Confirm Your PC’s Specs
Windows 10 has some minimum requirements for installation. Pretty much any modern PC should have no trouble meeting them, but if you’re trying to install Windows on an old computer, they may cause a hiccup.
Your processor must have a speed of at least 1GHz. Additionally, the 32-bit version of Windows 10 requires 1GB of RAM, while the 64-bit version requires 2GB. Make sure you’ve chosen 64-bit or 32-bit Windows as appropriate, too.
If you don’t meet these requirements, it’s time for a new computer. Windows 10 will not run smoothly at these bare minimums.
Troubleshooting Windows Installation Error Codes
Sometimes the Windows installer will fail with a specific error code. We look at some of these below and review the best steps for solving them.
Errors Starting With 0xC1900101
Any error that starts with this code is typically related to drivers. Make sure you’ve unplugged unneeded devices as mentioned above. Follow our guide to updating drivers and make sure crucial drivers, like graphics and chipset, are current.
You should also open the Device Manager by right-clicking the Start Button and choosing its entry on the resulting menu. Look for any devices with a yellow exclamation point icon beside them. Update the drivers for these devices or remove them if you don’t need them. Then try the installation again.
This usually signifies that the update process didn’t complete successfully due to a power issue. When you try again, make sure your PC stays powered on the entire time. Plug it in if it’s a laptop, and avoid running the upgrade when your electricity may go out.
Error 0xC1900208 – 0x4000C
If you see this error, you likely have an incompatible app on your PC that’s blocking the installation. Uninstall any ancient apps you might have around, then try again.
This error appears when your computer can’t connect to the Windows Update servers. Disconnect from any VPNs and join a more reliable network, if possible.
Generic Error Messages
Error messages like We couldn’t complete the updates. Undoing changes. Don’t turn off your computer and Failure configuring Windows Updates. Reverting changes don’t provide you with any specific information.
To see what happened, you’ll need to search in the Start Menu for update history and choose View update history. Look for the latest failures, note the error code, and Google it to see what’s up.
Windows Installation Made Easy
Unfortunately, it’s impossible to diagnose every possible Windows installation error in a general guide. But hopefully, these pointers let you rule out some causes and get the root of your issue. If not, you’ll likely need to dig into some more information about your specific error code.
To learn more about fixing problems like this, check out our introduction to Windows troubleshooting.