News

Microsoft: Windows 10 'Folder Redirection' Caused October 2018 Update Woes

• By Kurt Mackie
• October 09, 2018

The cause of Microsoft's flawed Windows 10 version 1809 release last week is the operating system's "Known Folder Redirection" feature, the company said in an explanation on Tuesday.

Some users reported missing files when they upgraded to Windows 10 version 1809, also known as the "October 2018 Update." John Cable, director of program management for Windows servicing and delivery, explained that the issues were caused by Windows 10's Known Folder Redirection" feature, which is supposed to redirect files stored in default Windows 10 folders -- such as "Desktop, Documents, Pictures, Screenshots, Videos, Camera Roll, etc." -- to those same "known folders" on a different drive or on the OneDrive storage service.

Users who lost files typically had Known Folder Redirection set up, but the files hadn't been moved, Cable explained. However, when Windows 10 version 1809 was installed on those users' systems, it deleted the known folders containing the actual unmoved files, resulting in data loss for those users.

The users who got hit with the file loss typically had selected "Check for Updates" within the Settings area of Windows 10, which immediately initiated a delivery of new updates to their systems, including an installation of version 1809. Cable suggested that only a small number of these users were affected by the lost files issue. It happened to "one one-hundredth of one percent of version 1809 installs," he indicated.

In response, Microsoft paused the OS rollout two days after the release of Windows 10 version 1809, Cable indicated. Data loss is considered to be a serious consequence, but the problem wasn't flagged highly for Microsoft because of the small number of affected users, Cable suggested. Consequently, Microsoft plans to add a new feature to the Windows Insider Feedback Hub that will let users grade the "impact and severity" of a software flaw, Cable explained.

Other reports, like this one, have suggested that Microsoft actually pulled back its Windows version 1809 release on Saturday, Oct. 6.

Windows on Hold for Now
Cable outlined three scenarios where such file loss had occurred. Microsoft has made changes to Windows 10 version 1809 that will address each of those problem areas, he promised. However, it is holding back on releasing the new operating system generally until further testing is completed. Microsoft is continuing to hold back not just Windows 10 version 1809, but also Windows 10 IoT and Windows Server 2019 to address the software flaws.

The fixed versions of Windows are getting floated in Microsoft's Windows Insider Program, which is a program for software testers. Microsoft plans to re-release the new OSes after getting testing feedback.

"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," Cable noted, although he didn't indicate timing.

Data Restoration?
Things could get tough for Windows 10 version 1809 users who lost data. Microsoft is working with them to recover the lost files, but it isn't offering any guarantees that their data will get restored.

Here's Microsoft's statement on its support for affected Windows 10 version 1809 users:

To help our customers that may be impacted by this issue, Microsoft Support is assisting 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.  While we cannot guarantee the outcome of any file recovery work, if you have manually checked for updates and believe you have an issue with missing files, please minimize your use of the affected device and contact us directly at +1-800-MICROSOFT or find a local number in your area. For more information, please refer to our Windows 10 update history page (KB article), which we are updating with new information as it is available.

Microsoft's "Windows 10 Update History" page also contains similar advice for affected users. It notes that Microsoft will provide a notice when the Windows 10 version 1809 rollout resumes.

Possibly, the Known Folder Redirection feature in Windows 10 version 1809 is similar to the "Known Folder Move" feature of OneDrive, since the problem affected some users moving files to OneDrive. Microsoft had previewed Known Folder Move for OneDrive for Business back in June. It lets IT pros enable file moves to known folders via Group Policy settings. Microsoft's documentation also refers to a Folder Redirection technology that sounds similar.