Last week Microsoft paused the rollout of the Windows 10 October 2018 Update (version 1809) for all users as follwoing reports of users missing files after updating. With the release of the new version to Windows Insiders, Microsoft wants to study the results and diagnostic data before taking additional steps towards re-releasing more broadly.
Microsoft says it has identified and fixed all known issues in the original update, and conducted internal validation. The issue
occurred if Known Folder Redirection (KFR) had been previously enabled, but files remain in the original "old" folder location vs being moved to the new, redirected location. KFR is the process of redirecting the known folders of Windows including Desktop, Documents, Pictures, Screenshots, Videos, Camera Roll, etc. from the default folder location, c:\users\username\<folder name>, to a new folder location. In previous feedback from the Windows 10 April 2018 Update, users with KFR reported an extra, empty copy of Known Folders on their device. Based on feedback from users, Microsoft introduced code in the October 2018 Update to remove these empty, duplicate known folders. That change, combined with another change to the update construction sequence, resulted in the deletion of the original "old" folder locations and their content, leaving only the new "active" folder intact.
Today, Microsoft also released some other fixes in the monthly update (KB 4464330) for its customers who have already taken the Windows 10 October 2018 Update.
Microsoft Support is assisting its customers and trying to recover data for users who may have experienced related data loss. Microsoft retail stores support services also offer this same level of support in-store. If you have manually checked for updates and believe you have an issue with missing files, minimize your use of the affected device and contact Microsoft directly at +1-800-MICROSOFT or find a local number in your area.
Microsoft will continue to monitor the update and all related feedback and diagnostic data from Windows Insider community. "Once we have confirmation that there is no further impact we will move towards an official re-release of the Windows 10 October 2018 Update," said John Cable, Director of Program Management, Windows Servicing and Delivery.