How to uninstall KB5063878 to fix SSD disappearing issue on Windows 11

• Windows 11 24H2 update KB5063878 (build 26100.4946) can cause SSDs (and even HDDs) to disappear under sustained writes over ~50GB, especially when disks are 60 percent full, risking data corruption or permanent failure.
• Microsoft and Phison are investigating, and users should postpone the update, back up data, and uninstall it if already installed.

On August 12, 2025, Microsoft rolled out the Windows 11 24H2 security update KB5063878 (build 26100.4946). Almost immediately, reports began emerging, especially from Japanese users, of a critical storage issue, which includes Solid State Drives (SSDs) disappearing under sustained write loads of roughly 50GB (and higher), particularly when the drive is over 60 percent full.

In independent testing, 12 out of 21 SSD models failed, including a WD SA510 2 TB that became unrecoverable even after reboot. While many drives reappear after a restart, the higher-risk “NG Level 2” cases involve potential data corruption or permanent drive failure.

The affected models are diverse, not limited to Phison NAND controller-based SSDs. They include devices from WD (Blue SN5000), Corsair (MP510 and MP600), Solidigm (P44 Pro), ADATA (LEGEND 800), Samsung (980 PRO 2TB), SanDisk Extreme Pro, Kioxia, Adata SP580, SK hynix Platinum P41, and more.

It’s important to note that this issue affects not only SSDs (and NVMe drives) but also Hard Disk Drives (HDDs).

Both Phison and Microsoft have acknowledged the reports and are investigating in coordination with hardware partners, though the software giant has not yet officially noted it as a known issue on the Windows Release Health page. Microsoft only said, “We’re aware of these reports and are investigating with our partners.”

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In the meantime, users are strongly advised to avoid large file transfers, delay installing KB5063878, and secure critical data using robust backup strategies. At this time, it’s also recommended to uninstall the update, as it may not undo damage already done.

In this guide, I’ll outline the steps to uninstall the KB5063878 update from Windows 11 to prevent it from breaking your system’s hard drive.

Uninstall update KB5063878 from Windows 11 24H2

To uninstall the KB5063878 update, follow these steps:

1. Open Settings on Windows 11.

2. Click on System.

3. Click the Optional features page.

4. Click the “More Windows features” settings under the “Related settings” section.

   

5. Click the Windows Sandbox option (if applicable).

   

   Quick note: Turning this feature off may prevent the error 0x800F0825 while uninstalling the KB5063878 update.

6. Click the OK button.

7. Click the Restart now button.

8. Open Settings one more time after the reboot.

9. Click on Windows Update.

10. Click the Update history page.

11. Click the Uninstall updates setting under the “Related settings” section.

    

12. Click the Uninstall option to remove the update KB5063878 (build 26100.4946) from Windows 11.

    

13. Click the Restart now button.

14. Open Settings one more time.

15. Click on Windows Update.

16. Click the “Pause for 1 week” button to disable automatic updates to prevent the system from reinstalling the update.

    

17. (Optional) Click on System.

18. Click the Optional features page.

19. Click the “More Windows features” settings under the “Related settings” section.

20. Check the Windows Sandbox option to re-enable the feature (if applicable).

    

21. Click the OK button.

22. Click the Restart now button.

After you complete the steps, the problematic update will be removed from the device, preventing the storage drive from disappearing.

Once the problem has been resolved, it’s critical to resume updates to continue receiving system and driver updates.

Recovery after storage has disappeared

If the update has already been applied and your device has come across this problem, you can try uninstalling the update using the steps above. However, if you’re experiencing data loss, unless a permanent fix is available that also provides a way to recover your data, you’ll have to restore your data from a previous backup.

Backup, backup, always backup

Although this problem is not affecting every hardware configuration, it’s yet another reminder of the importance of maintaining a full backup of the entire device as well as a separate backup of your files.

You have multiple ways to approach your backup plan. You can use the legacy System Image Backup tool to create a full copy of your computer. You can also use the automatic backup feature on Windows 11, and you can back up your files using File History, Windows Backup, and OneDrive.

If you want to prevent a similar scenario in the future, you should consider disabling automatic updates on Windows 11 and scheduling a manual system update around two weeks after the official release of a cumulative update if there are no signs of problems with the specific release.