I am attempting to update from 1803 to 1903 on a minimum (32GB) Acer laptop and getting failure. The process is identical to that previous used successfully. On a minimum machine, connect a USB expander. One USB contains the Windows bootable source, the other a blank 16 GB stick for scratch files. Boot the machine, run setup from the bootable USB, inform setup to use the empty scratch USB. Allow setup to run. For previous updates the process takes ~ 1 hour or so, eventually installing the update.
Alas, not for 1903. It goes all the way to the full blue area with 1% completed and stays there. No progress for several hours. Eventually it reboots, uninstalls whatever it has done, reboots back to 1803. Obviously setup found it couldn’t proceed but there are no entries in the events files to indicate the issue.
Perhaps it can’t be done on this machine. I did some research that suggests trying https://docs.microsoft.com/en-us/windows/deployment/upgrade/setupdiag to identify why setup can’t complete.
Have others been successful? Any tips other than the setupdiag tool?