After that, I took some time using Media Creation tool to create DVD for installation. It may have solved some cases, but not this one. When automatic update had failed several times, it was time to try Windows Update Assistant. After trying all that and a lot more, I also chose to update my motherboards and SSD's firmware as suggested in some sources.
but according to my experience it's nonsense. Some sites suggest disabling Intel virtualization etc. Lots of articles suggest removing 3'rd party antivirus software, external devices etc. When automatic update fails, there are some alternative solutions. That was the main reason to keep trying, installing all the app´s again was not an option. All my software and app's are still in place. So it took several months to succeed, but finally today () I got my Windows updated to 1803 and no clean install was needed. Since April 2018, My Windows 10 has been trying to update itself to version 1803 and every single time the update has failed.
Symptoms: Installation stops at 86% no matter what, reverts back to 1709 and gives an Error Code: 0xC1900101-0x4001E 'The installation failed in the SECOND_BOOT phase with an error during PRE_OOBE operation' Maybe other upgrades too? Provisioning may be the reason for the failure. Windows 10 upgrade from 1709 to 1803 fails.
