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Hello,
Microsoft is aware some customers are unable to install Windows 8.1 due to error 0xC1900101 -0x40017.
This error indicates a failure to boot Windows 8.1 occurred during the final parts of the update, causing the system to roll back to Windows 8. The most likely cause of this error is an incompatible driver or hardware defect. Unfortunately, due to the timing of this failure, there are often no logs, crash dumps or other diagnostic information available to investigate the issue easily, which makes it difficult to determine which, if any, of the drivers or system components are causing the update to fail.
We are currently working with the companies that develop these drivers to help them update their problematic drivers whenever they are identified. Some of the identified drivers have been listed in the original post, however due to the sheer number of drivers constantly being created by other companies all over the world, this is a daunting task. We understand that the inability to easily identify the incompatible driver can be incredibly frustrating and we are sorry for the inconvenience.
Make sure you’ve installed all the latest Windows Updates and latest drivers from your hardware and software manufacturers. You can also try uninstalling any unnecessary hardware or software prior to updating to Windows 8.1.
If your hardware and software manufacturers do not have updated drivers and you are experiencing this error, the best method for upgrading to Windows 8.1 is to clean install Windows 8, and then update to Windows 8.1 before allowing any additional drivers or software to install.
To do this:
- Back up all of your personal documents and data to an external drive.
- Disconnect your computer from the Internet.
- Perform a clean install of Windows 8 using Windows 8 installation media (DVD or USB). For help performing a clean install of Windows, see How to perform a clean install of Windows.
Note: If you do not have media and Windows 8 was pre-installed on your PC, please contact your PC manufacturer for assistance. Otherwise to get help obtaining installation media, contact Microsoft Support. 4. Once you’ve reinstalled Windows 8, change your hardware settings so that you do not automatically install driver updates.
**>>**From the Start screen, type “System”, and then click on “View advanced system settings” in the search results. This will open the System Properties dialog.
**>>**Click on the Hardware tab, and then click Device Installation Settings.
**>>**When the Device Installation Settings window appears, click the “No, let me choose what to” button, and then “Never install driver software from Windows Update”. Click Save Changes to save the setting. 5. Reconnect your computer to the Internet. 6. Install Windows Updates. Restart the computer when prompted. 7. Open Windows Store and install Windows 8.1. 8. Afterwards, be sure to restore your hardware settings so that your device drivers once again install automatically. (Repeat Step 4, but restore this setting to “**Yes, do this automatically (recommended)”**and Save changes.)