If your Windows 11 machine has been mysteriously running out of drive space and you haven’t been able to figure out why, you may not be imagining things, and it may not be your fault.
Microsoft has confirmed a storage bug tied to Windows 11’s Capability Access Manager, the system service that tracks and manages app permissions for things like your camera, microphone, and location. The culprit is a file called CapabilityAccessManager.db-wal, a write-ahead log that’s supposed to stay a few megabytes but can, under this bug, balloon into the hundreds of gigabytes. Some affected users have reported the file consuming over 500GB on its own.
Microsoft’s official fix arrives via KB5095093, which shipped as an optional preview update on June 23 and is set for full automatic rollout through July’s Patch Tuesday. The acknowledgment itself is almost comically understated: the release notes simply read, “This update improves disk space usage for the CapabilityAccessManager.db-wal file,” with no mention of the scale of the problem or a public explanation of the root cause. The bug was first surfaced by Windows Latest and community reports on Reddit and Microsoft’s own support forums, not by Microsoft proactively flagging it.
If you want to check whether you’re affected before the patch lands: run robocopy "C:\ProgramData\Microsoft\Windows\CapabilityAccessManager" "%TEMP%\CAMCheck" /L /B /R:0 /W:0 /BYTES /NP from an elevated prompt and look at the size reported for CapabilityAccessManager.db-wal. A few megabytes is normal. Multiple gigabytes, and climbing, means you’ve likely been hit. The folder itself is protected, so don’t try to poke around it directly in File Explorer, and resist the urge to just delete the file manually. Install KB5095093 through Windows Update’s optional updates section instead, or wait for it to arrive automatically next week.
One open question nobody, including Microsoft, has fully answered yet: does the update actually reclaim space an already-bloated file has consumed, or does it just stop the file from growing further going forward? Based on the available reporting, that’s unclear, and Microsoft’s terse release note doesn’t clarify it either way. If your drive is already full because of this, install the update, then re-check the file size afterward rather than assuming your storage is automatically restored.
This isn’t a headline-grabbing exploit or a security hole. It’s the more mundane, more common kind of Windows bug: a background service quietly misbehaving for what reporting suggests has been the better part of a year before anyone at Microsoft owned up to it publicly. If your SSD has felt suspiciously tight lately for no obvious reason, this is worth ten minutes of your evening to check.
Discussion (5 replies)
Join Discussion →Between this and Google's AI, you really have to keep track of things these days. Whoosh, 1 TB gone before you know it.
At least once a week a see a story that confirms I bailed on Microslop at the right time. I was an Amiga user forced to IBM compatible to play games. That wound will never heal. 💀 The GN vid with Wendell about peak microslop last week was another zinger.
What were the PC specs you had to settle for? I know the AmigaOS was far ahead of its time and advanced in many ways. Glad I never used it otherwise I would long badly for it too.
It's been more than half a lifetime ago. I think Pentium 60? iGPU on the board for video? Packard Bell POS. Windows 3.11 for workgroups? I was not rolling my own yet.
At least you started off good. I had a 386DX-40 and 486DX2-66 before I got a Pentium 166 (or 133) non-MMX and it wasn't until the Pentium II 350 MHz that I felt the PC was sufficiently fast though the Pentium wasn't horrible and I did buy a used one while I was living in a shared space so other guys wouldn't hog my Coppermine Celeron PC (same Pentium II one, just upgraded to Celeron 700) and the Pentium was surprisingly usable.