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Arthur T Knackerbracket has found the following story [bleepingcomputer.com].
Reports are coming in that the Windows 10 KB4532693 cumulative update is loading an incorrect user profile and causing the user's desktop and Start Menu to be reset to default.
On February 11th, Microsoft released the Windows 10 v1909 and v1903 KB4532693 cumulative update as part of their February Patch Tuesday [bleepingcomputer.com] updates.
Since then, reports are starting to come in that after installing the update, some users state that their normal user profile is missing, their desktop files are missing, and everything was reset to default.
I first learned about this when a user posted in our Windows 10 Cumulative Updates KB4532693 post [bleepingcomputer.com] stating that their brother's computer experienced this problem after installing the update.
After doing some research, I also saw similar issues being reported in the Microsoft forums [1 [microsoft.com], 2 [microsoft.com], 3 [microsoft.com]] where users installed the update and after logging in found their desktop files missing and the Start Menu reset.
"Hello. Sorry to post a random question here, but a bit new at this. Just installed the latest Feb 2020 Windows 10 updates. Upon completion it appears to have reset the display to default windows system. That is, all custom icons missing, background returned to windows logo, would not recognise my logon, set a temp logon."
Günter Born of Borncity posted [borncity.com] about this problem happening to some of his readers and also linked to a different Microsoft Forums post [microsoft.com] titled "why has the latest windows update moved all my files into another user folder ending in .000?"
Born also mentions a tweet by Woody Leonhard where someone had experienced a similar issue.
In this case, a family member's account was being loaded into a temporary profile and their original profile had been renamed. After some Registry editing and folder renaming, the user was able to recover the profile and get things back to normal.
Based on the reports by affected users, it appears that a bug in the KB4532693 update is loading up a temporary profile to be used during the update process and failing to restore the user's profile when done.
The good news is that the update is not wiping your data, but rather renaming the original user profile in the C:\Users folder. If you are affected by this issue, you can look in C:\Users and see if you have a renamed profile ending in .000 or .bak.
Unfortunately, restoring a profile through Registry edits may be a very difficult and risky task for many people.
As some people stated that they could resolve the issue by restarting Windows a few times or uninstalling the KB4532693 update, it is safer to go down this route first if you are affected by this issue.
BleepingComputer has reached out to Microsoft for more answers but has not heard back as of yet.