If you follow any of the computer trade magazines and web sites, you've probably seen that the Windows 10 version 1809 feature update made the news in a not-so-good fashion. On Tuesday, October 2, Microsoft released feature update 1809 and pulled it four days later, October 6, because of a number of complaints that it deleted customer data. One user, Robert Ziko, reported "I have just updated my windows using the October update (10, version 1809). It deleted all my files of 23 years in amount of 220GB. This is unbelievable,"
What the heck happened? According to Microsoft's John Cable, Director of Program Management, Windows Servicing and Delivery, the original problem occurred on systems where Known Folder Redirection (KFR) was previously enabled but some files still remained in the original location. For example, if you moved the Documents folder from its location in your user profile to a new location, such as a secondary data drive, but left some files in the old location, the setup logic for the version 1809 upgrade removed the folder in the old location as well as all of the files in it. The problem also occurred on some systems using the relatively new Auto Save feature in OneDrive to relocate the contents of the Desktop, Documents, and Pictures folders to corresponding locations in the cloud. Here, too, the bug fired if some files remained in the old location.
The good news is that Microsoft now reports "We have fully investigated all reports of data loss, identified and fixed all known issues in the update, and conducted internal validation. Also, Microsoft Support and our retail stores customer service personnel are available at no charge to help customers." instead of immediately making the updated bits available to the public, Microsoft says it's limiting the initial release of this update to devices that are part of the Windows Insider Program. Devices configured for the Slow and Release Preview rings should receive the new build.
If you happen to be one of those who installed the original update without issue, Microsoft released the first cumulative update for 1809 as part of their scheduled Patch Tuesday. It incorporates a few additional fixes, including a fix for a bug that incorrectly deleted user profiles on systems with a specific Group Policy enabled. More details are available in KB4464330. The cumulative update takes Windows 10 to version 17763.55. Also included is a new servicing stack update for Windows 10 version 1809, documented as KB4465477.
Microsoft says the number of customers impacted by the bug was small, with "reports of data loss" limited to "one one-hundredth of one percent of version 1809 installs." If this estimation is accurate, it translates into a few hundred systems that were affected by this bug. The company says it will offer data recovery options to affected users but cannot guarantee the outcome of any such recovery efforts.
So, what can YOU do to prevent data loss like this? In a word, Backup"¦let me repeat that, MAKE REGULAR BACKUPS!! There are always going to be situations where data loss is possible, many are simply unavoidable. A good, recent, backup will keep your data safe.