How To Fix Windows 10 upgrade assistant stuck at 99% | Windows101Tricks | Scoop.it
From howtofixwindows.com - December 14, 2017 10:51 AM

While upgrade to Windows 10 fall Creators update using Upgrade Assistant the upgrade process Stuck at 99% for Long time ? this is because Downloaded Update files are damaged or corrupted, System or boot partition fail to load. Here some applicable solutions to fix this issue http://howtofixwindows.com/fix-windows-10-upgrade-assistant-stuck/