i did the obligatory google searches and i jumped through all (?) the hoops, failing a solid 10 or more times, and yes, that’s at about 40 to 45 minutes per failed attempt. Re failure code 0xc1900101 – 0x20017 during windows upgrade to 10: i found the solution on my system after over 10 attempts. when i tried to upgrade to windows 10, i constantly got the error: we couldn't install windows 10. disconnect all usb devices from your computer remove the wifi adapter. wait for the dialogue confirming restore point creation. then click create, specify the name of a restore point click ok and confirm it.
To create a system restore point hold down the windows key and press r on your keyboard. to fix the problem, you need to modify your registry by doing the following: press windows key r and enter regedit. if you’re having windows 10 installation errors 0xc1900101 or 0x20017, the problem might be related to your registry.