14 DAY TRIAL // It's not a secret that the upgrade from Windows 7 or 8.1 to Windows 10 isn't going as smoothly as it was supposed to, and many of the users who are trying to benefit from the free upgrade offer are actually encountering various errors that prevent them from installing the new OS.
Today, Microsoft publicly acknowledged one of these errors, saying that it's still working on fixing it, so a resolution should be provided in the coming days or weeks.
Error 0xC1900101 – 0x30018 is causing Windows 10 installation to fail, with the computer to then be rolled back to the previous operating system with one of the two errors: “We couldn’t install Windows 10. We’ve set your PC back to the way it was right before you started installing Windows 10” or “The installation failed in the FIRST_BOOT phase with an error during SYSPREP operation.”
Incompatibilities very likely at fault
According to Microsoft, which confirmed in a post on the Community forums, the problem is most likely caused by incompatibility issues with antivirus or other security programs on your computer, or because of drivers or hardware that's not fully compatible with Windows 10.
“We are currently working with our partner companies to help update problematic drivers whenever they are identified,” Microsoft said. “We understand that the inability to easily identify the incompatible driver can be incredibly frustrating and we are sorry for the inconvenience.”
Even though a fix is still in the works, Microsoft says that you could try disabling antivirus software or any other application that you suspect could be at fault for the problem, switch from Wi-Fi to a wired connection, remove USB devices except the keyboard and mouse, install all Windows updates on your previous Windows version and type “sfc /scannow” in a command prompt window to fix any damaged system files.
If none of these options works, you have to wait for the official fix that Microsoft should provide you with sometime in the coming weeks.