A recent Windows 11 update, identified as patch KB5063878, is reportedly causing major issues for some users, with a number of reports claiming it is causing solid-state drives (SSDs) to fail. The problem appears to be triggered during heavy write operations, particularly when transferring large files or game updates over 50GB. When the issue occurs, the SSD can become unrecognized by the operating system, and in some cases, the drive becomes unrecoverable.
While the bug doesn’t affect all drives, initial reports suggest that SSDs with Phison NAND controllers are more susceptible. The bug has been reported on various models from different brands, including Corsair and SanDisk. The problem seems to be related to a regression in the update’s code that mishandles long, sequential writes, causing the drive’s controller to lock up. While a simple PC restart can sometimes make the drive reappear, the issue can reoccur upon trying the same file transfer.
Microsoft has not yet officially acknowledged the problem or provided a fix. Users are advised to back up their data and avoid large sequential writes if they have installed the affected update. Until an official patch is released, a temporary workaround is to uninstall the KB5063878 update. However, this leaves systems vulnerable to the security issues that the update was meant to address. The community is currently working to gather more data and identify a permanent solution.