Microsoft has acknowledged a persistent bug in Windows 11 that results in the Capability Access Manager’s write-ahead log file expanding indefinitely, potentially consuming over 500GB of storage on impacted devices. This issue is addressed in update KB5095093, which includes builds 26200.8737 and 26100.8737. Users have the option to manually install this update via the optional updates section of Windows Update or wait for its automatic rollout during the July 2026 Patch Tuesday.
What Is Causing The Windows 11 Storage Bug
The Capability Access Manager plays a crucial role in Windows 11, managing app permissions and overseeing access to privacy-sensitive features such as the camera, microphone, location, contacts, and screen capture. It also logs requests and usage of these capabilities. The problem lies not within the permission system itself but with the CapabilityAccessManager.db-wal file, which serves as the write-ahead log for the database.
Under normal circumstances, this log file expands during regular use but is expected to be merged back into the main database. However, on affected systems, the WAL file continues to grow unchecked. Reports indicate that the file can balloon to sizes ranging from 70GB to 200GB, with some instances reaching an astonishing 513GB, as confirmed by TreeSize.
How To Check If Your PC Is Affected
To ascertain whether your system is impacted by this issue, consider the following methods:
- Method 1: Check Storage Settings: Navigate to Settings, then System, and select Storage. Click on Show more categories to view the size allocated for System and reserved storage. If System files display hundreds of gigabytes, your system may be affected.
- Method 2: Use Robocopy for Direct Verification: If the System and reserved storage appears elevated but not excessively so, you can verify the file directly. Open an elevated Command Prompt and execute a command to list files in the relevant folder. Look for CapabilityAccessManager.db-wal in the output. If it shows only a few megabytes, your system is likely unaffected. However, if it is several gigabytes and continues to grow, the bug may be present.
The fix is encapsulated in KB5095093, which includes build 26200.8737 for Windows 11 25H2 and 26100.8737 for Windows 11 24H2. To install the update, follow these steps:
- Open Settings
- Go to Windows Update
- Select Advanced options
- Choose Optional updates
- Locate KB5095093 and follow the prompts to install it
- Restart your device if prompted
For those who prefer to wait, the update will be automatically included in the cumulative update scheduled for July 8, 2026, during the Patch Tuesday rollout. After applying the fix, the WAL file should return to its normal behavior, although a system restart may be necessary for changes to take effect.
How To Fix The Capability Access Manager Log Issue
For users with SSDs, particularly those with limited capacities of 512GB or 1TB, a WAL file consuming hundreds of gigabytes can lead to critical storage shortages. This situation can trigger various issues, including application installation failures, incomplete Windows Updates, frequent temporary file cleanups, and failed backup or restore operations.
Users experiencing these symptoms without a clear cause should specifically examine the CapabilityAccessManager.db-wal file, as standard storage cleanup tools may overlook it. KB5095093 is currently available through the Optional updates section of Windows Update and is anticipated to be more broadly distributed with the upcoming July 8, 2026, Patch Tuesday cumulative update. The fix applies to Windows 11 versions 24H2 and 25H2.
Microsoft has not yet confirmed whether Windows 11 26H1 Insider builds are affected. Users on Insider channels should remain vigilant for similar fixes in forthcoming Insider flight releases. Those noticing significant unexplained storage usage are encouraged to install the update promptly. While the bug does not compromise the security or core functionality of the permission system, the excessive file size can severely limit available storage on affected systems.
