Today, Microsoft is releasing a fixed version of the Windows 10 October 2018 Update to Windows Insiders for the critical deletion bug. In a blog post, Microsoft's John Cable, Director of Program Management, Windows Servicing and Delivery confirmed that the bug that caused the removal of files on the certain system has been addressed and Windows 10 October 2018 Update is once again available to the Insiders.

Microsoft says that they have analyzed all reports of data loss and conducted an internal investigation to find out the cause of the files removal. According to Microsoft, a very small number of users lost files after installing Windows 10 October 2018 Update and it occurred on systems that had Known Folder Redirection (KFR) enabled, but files remained in the original “old” folder location vs being moved to the new, redirected location.

"Prior to re-releasing the October 2018 Update our engineering investigation determined that a very small number of users lost files during the October 2018 Update," stated the Microsoft announcement. "This 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\, 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," explains John Cable, Director of Program Management, Windows Servicing and Delivery, Microsoft. "Based on feedback from users, we 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".

This fixed version of the Windows 10 October 2018 Update is first being made available to Insiders for final testing and after analyzing the feedback and data from the Insider community, Windows 10 October 2018 Update will be re-released to the general public soon.

"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," Microsoft explains.

Workaround to recover the deleted files

Microsoft has stated that they are using file recovery tools to recover user's deleted files. Therefore, they are suggesting that users use their PCs as little as possible so that deleted files are not overwritten with new data.

For those who are affected, they should call Microsoft at +1-800-MICROSOFT or find a local number in your area.

Improvements to Feedback app

Microsoft is also updating the Feedback app in Windows 10 to enable a new feature that would allow Insiders to provide an indication of impact and severity when filing feedback. This would allow Microsoft to monitor both critical issues and features suggestions.

"To help us better detect issues like this, today we have enabled a new feature in the Windows Insider Feedback Hub," stated the blog post. "We have added an ability for users to also provide an indication of impact and severity when filing User Initiated Feedback. We expect this will allow us to better monitor the most impactful issues even when feedback volume is low."

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