Microsoft has found a novel way to make your SSD feel smaller without actually changing its capacity. A Windows 11 storage bug has been causing a normally tiny system database log to balloon into tens or even hundreds of gigabytes, with one reported case topping 500GB. The culprit is a file called CapabilityAccessManager.db-wal, part of the Windows Capability Access Manager system used to track application access to privacy-sensitive resources including the camera, microphone, location services and screen capture.
On a healthy machine, the file should generally be measured in megabytes. On affected systems, users have reported sizes ranging from around 12GB to 200GB, with one widely reported case reaching roughly 500GB. That is enough to consume half of a 1TB SSD simply because Windows apparently became overly enthusiastic about keeping notes on who asked to use the microphone.
Microsoft has now addressed the problem in optional Windows 11 preview update KB5095093, released on June 23 for Windows 11 versions 24H2 and 25H2. In typically understated fashion, the company describes the change simply by saying the update “improves disk space usage for the CapabilityAccessManager.db-wal file.”
Microsoft added that storage item to the update changelog on June 29, but has not provided a detailed public explanation of the failure or the scale of the storage consumption reported by some users. That rather mild description does not quite capture the experience of discovering that Windows has quietly misplaced several hundred gigabytes of your SSD.
The affected file is a write-ahead log associated with the Capability Access Manager database. In normal database operation, this type of log records changes before they are committed back into the main database. It can grow temporarily, but it is not supposed to keep expanding until it competes with a large Steam library for control of the system drive.
Reporting from Windows Latest suggests the runaway growth may be linked to Windows repeatedly logging permission and privacy-access events while the log is not being properly merged or compacted back into the main database. Microsoft itself has not publicly confirmed that as the root cause, so for now the exact mechanics remain less transparent than the missing free space.
Part of what makes the problem particularly irritating is that it can be difficult for an ordinary user to identify. Windows may account for the consumed capacity under System & reserved storage rather than pointing directly at the offending file. Someone watching the free space on the C: drive slowly disappear could reasonably blame installed applications, games, temporary files or years of questionable downloading decisions before suspecting an obscure Windows permissions database.
The first place to look is Settings > System > Storage > Show more categories > System & reserved. If System files are occupying an implausibly large amount of space, the machine may be affected.
The file itself lives at:
C:\ProgramData\Microsoft\Windows\CapabilityAccessManager\
Checking it directly is not always straightforward because the folder is protected and may return an access denied error even when using administrative tools. Disk-analysis utilities including TreeSize, WizTree and WinDirStat can help identify oversized files when run with appropriate privileges.
Windows Latest also documented a read-only Robocopy command that can list the contents without changing folder ownership or permissions:
robocopy "C:\ProgramData\Microsoft\Windows\CapabilityAccessManager" "%TEMP%\CAMCheck" /L /B /R:0 /W:0 /BYTES /NP
On an unaffected system, CapabilityAccessManager.db-wal may be only a few megabytes. If it is measured in multiple gigabytes or continues growing rapidly while the machine is running, something has clearly gone off the rails.
Users should resist the temptation to start casually deleting protected system database files. Reports indicate that manually interfering with Capability Access Manager components can cause unintended problems, including connectivity trouble. The safer approach is to install the update Microsoft has provided rather than attempting some home-grown database surgery on a live Windows installation.
KB5095093 is currently available as an optional preview update for Windows 11 24H2 and 25H2. Microsoft’s official support documentation lists OS builds 26200.8737 and 26100.8737 for the release. Users who need the fix immediately can check Windows Update and the optional update section, while the change is expected to reach the broader Windows 11 population through the regular July 2026 update cycle.
The fact that something buried deep inside Windows can grow to the size of a game library without throwing up a meaningful warning is not exactly a great advertisement for Microsoft’s storage management. Nor is quietly slipping the fix into an optional preview update with a changelog entry that sounds more like routine housekeeping than a potentially massive disk-space problem.
Microsoft so far has fixed the bug, which is the important part. But for users who spent days wondering where their SSD space had gone, the experience is another reminder that Windows 11 can still produce some spectacularly strange failures in places nobody thinks to look.
Windows 11 has been called bloated for years. This time, a runaway database log proved the point by eating half a terabyte and leaving users to figure out where dinner went.
