Wonder if it is related to the new onedrive system they are implementing that "automatically" identifies files you don't use often and moves them to onedrive - I'd hope that was off by default though but I can see that going badly wrong and/or people imagining their files are deleted when they are in dropbox. Didn't think it was active yet though.
EDIT: That link tends to confirm it is related to that... if so that is truly utterly facepalm worthy of MS and they really need to start firing people and bringing in developers with actual vision who can foresee these issues :|
I know someone that can't get it installed from 1803 to 1809 build, does the download and gets to the 15% after reboot and says undoing changes, goes back to desktop after awhile and says
Error - 0x80070004 - 0x2000D the installation failed in the safe_os phase with an error during migrate_data operation.
This is via Windows update and media creation tool via USB , also tried with Windows 10 Upgrade Assistant, scratching my head on how to fix this, got the feeling this update was rushed through the door without proper testing.
No file or registry/HD errors, memory is fine, all drivers installed, so this will be fun and games to fixed
.
I did install 1809 version fine on my laptop so going to try my desktop PC next and see if that gets any issues, got a feeling I should stay on 1803 build since that is running sweet for me with zero issues, sometimes it pays to wait.
I wonder how many more bugs/issues they will find, they should really do more testing on their new Win10 final builds if they want users to stay with 10.