First noticed by Neowin, the scale of the serious issue is revealed by a Reddit thread that now has over 600 replies. No single cause for the freezing has been established. The users are all experiencing the same consequences: a total system lock-up at seemingly random intervals.
The freezes usually trigger very soon after turning the PC on. The original poster in the Reddit thread said his computer is usable for little more than 20 seconds. After that, hovering the mouse over the Start menu or taskbar leaves the entire system unresponsive.
The only way to recover from the bug is to reboot the PC. This allows for another 20 seconds of usage before it freezes up again. The period of time before the computer will freeze varies for each individual.
The bug has been observed to occur across a wide range of hardware configurations and form factors. It persists after disabling third-party startup programs, indicating the problem is caused by system code introduced with the Anniversary Update.
A variety of fixes have been suggested by various users. So far, there doesn’t seem to be a general solution though. Some procedures work for some people but produce no results for others.
One popular idea is to move the locations of the app installation and user files directories back to the system drive. This is only applicable to people that have previously moved the location of these folders. Other suggestions include updating Intel Rapid Storage technology and installing the Anniversary Update from an ISO file rather than a download.
After staying quiet for a while, Microsoft has now responded to the rapidly increasing number of reports. The @MicrosoftHelps Twitter account acknowledged the company is aware of the problems and directed affected users to seek assistance on its support forums.
In a post on its support site, Microsoft suggested users run the System Maintenance Troubleshooter in a first attempt to fix the bugs. If that fails, it advises the computer is started in safe mode and then clean booted to disable third party software. Replies in the Reddit thread already indicate this approach doesn’t always work however.
With Microsoft now admitting to the issues, its engineering teams should begin diagnosing the cause of the problems. It can then be patched in an upcoming update, although with some PCs unusable for more than a few seconds Safe Mode may again be required.
This isn’t the first major issue to appear since the launch of the Windows 10 Anniversary Update. Other problems include severe bugs when using Xbox One controllers in games and the inability of some laptops to update at all. They end up stuck in a reboot loop and displaying a black screen. While the update has been extensively tested internally and with Windows Insiders, it looks like Microsoft could have done better on quality control.
