I first tried to install Windows 10 update Version 1809 twice on 4th October 2018 with message 0xc1900101.
A couple of days after my failed second attempt I learned of issues with this update so I stopped trying until mid-December.
I have lost track of the number of failed attempts since then.
Windows Update does not recognise that Version 1809 exists. I then tried using Windows 10 update assistant. Downloading V 1809 was fine but when it came to installing the update it failed at 42% of installation and would begin to undo the changes and bring me back to V 1803.
As stated, I tried many times without Windows 10 update assistant. I tried many times with the assistant as well but come the dreaded figure of 42% installation completion it would fail and begin to undo the changes and back to V 1803.
In my Update history the following is written:
Feature Updates (1)
˅ Feature update to Windows 10, version 1809 (2)
Last failed install attempt on 04/10/2018 - 0xc1900101
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