Wednesday, July 8, 2026
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A Windows 11 bug is silently eating up to 500GB of storage space

3 min read Editorial
  • Status: Confirmed / Fix Available
  • Affected Builds: Windows 11 OS builds 26200.8737 and 26100.8737 (and likely others)
  • KB Article: KB5095093

If your Windows 11 drive seems to be filling up without any obvious cause, you might be dealing with a specific system bug. Microsoft has acknowledged an issue where a single database file related to app permissions can balloon in size, consuming hundreds of gigabytes of storage space.

The CapabilityAccessManager.db-wal bloat

The culprit is the CapabilityAccessManager.db-wal file. This file is part of the Capability Access Manager service, which handles permissions for apps in Windows. Under normal circumstances, this file should only take up a few megabytes.

However, on affected systems, this file can grow to several hundred gigabytes. In extreme cases reported by users, it has filled drives completely, leading to significant performance degradation and storage errors. The issue has been present for some time, with reports dating back nearly a year, but Microsoft recently addressed it in patch notes.

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The fix was noted in the release details for KB5095093, specifically mentioning improved disk space usage for this file on OS builds 26200.8737 and 26100.8737.

A screenshot-style illustration showing a disk usage analysis tool interface with a large red bar highlighting a single
Tools like WizTree or WinDirStat help users visualize hidden file sizes that standard Windows settings do not reveal.

How to check if you are affected

The standard Windows Storage settings (Settings > System > Storage) will not help you identify this specific problem. The interface shows overall drive usage but does not break down hidden system files in a way that highlights this anomaly.

To verify if your PC is suffering from this bug, you need to inspect the actual file size. You have two main options:

  • Use a disk visualization tool: Applications like WizTree, WinDirStat, or TreeSize can scan your drive and highlight large files. Look for the CapabilityAccessManager.db-wal file in the results. If it is several gigabytes or larger, you are affected.
  • Use Command Prompt: You can run a specific command to check the folder size without copying data. Open Command Prompt as Administrator and paste the following:

    robocopy "C:\ProgramData\Microsoft\Windows\CapabilityAccessManager" "%TEMP%\CAMCheck" /L /B /R:0 /W:0 /BYTES /NP
    This command lists the files in that directory to help you assess their size.

How to fix the issue

Microsoft has included a resolution for this bug in the June 2026 optional update. You can install it manually by navigating to Windows Update > Advanced options > Optional updates and looking for KB5095093.

If you prefer to wait, the fix will be rolled out broadly to all users in next month’s July Patch Tuesday update. Once installed, the system should manage the file size correctly again.

What this means for you

For everyday Windows users, this bug is a silent storage thief. It can make your PC feel sluggish or prevent new downloads and updates from installing due to lack of space, even if you haven’t installed many large apps recently.

Important warning: Do not manually delete the CapabilityAccessManager.db-wal file or attempt to uninstall the Capability Access Manager service. Doing so can cause further system errors and instability. Wait for the official update from Microsoft to resolve the bloat safely.

Source: PCWorld

Build details:

  • kb5095093

Over to you: Have you noticed unexplained storage loss on your PC recently, and did the optional update resolve it for you?

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Windows & Microsoft news editor at 9to5Windows. Covering everything from Windows 11 builds to enterprise updates.

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