Windows 11 users who have noticed their C: drive mysteriously filling up may finally have an explanation. Microsoft has confirmed a bug that can cause a protected system file to grow uncontrollably, consuming hundreds of gigabytes of storage without any obvious warning.
The issue affects a file named CapabilityAccessManager.db-wal, which is used by Windows to manage privacy and hardware access logging for features such as the camera, microphone, location services, and screen capture.
A Small File That Can Become Massive
Under normal circumstances, the file is only a few megabytes in size. However, affected systems have reported it growing to extraordinary sizes, including:
- Around 70GB
- More than 100GB
- Over 200GB
- As much as 513GB
The file is located in:
C:\ProgramData\Microsoft\Windows\CapabilityAccessManager\Because the folder is hidden and protected by Windows, many users never realize it is responsible for their disappearing storage space.
How to Check If You’re Affected
If your Windows 11 installation is unexpectedly reporting extremely high System files usage, you can check by opening:
Settings → System → Storage → System & reserved
If the System files category is showing unusually large amounts of storage—such as 100GB, 200GB, or more—the oversized database file may be the cause rather than downloads or installed applications.
Microsoft Has Released a Fix
Microsoft has addressed the issue in update KB5095093. According to the company’s release notes, the update improves disk space usage by preventing the CapabilityAccessManager.db-wal file from growing excessively.
The fix is also expected to be included in the July 2026 Patch Tuesday cumulative update, meaning most Windows 11 users should receive it automatically through Windows Update.
What You Should Do
If you’re experiencing unexplained storage loss on Windows 11:
- Check the System files category in Storage settings.
- Install update KB5095093, or ensure your PC is fully updated.
- Allow Windows Update to install the latest cumulative updates, including the July 2026 Patch Tuesday release.
Keeping Windows up to date should prevent the logging database from consuming excessive disk space in the future.
