Is your Windows 11 disk space disappearing with nothing to show for it — tens or even hundreds of gigabytes gone, and Storage settings blaming vague “System & reserved” files? There is a good chance a single hidden database log file is responsible. Microsoft has now quietly acknowledged the bug and shipped a fix, but installing the fix alone does not always give you the space back. Here is how to check whether your PC is affected and how to reclaim the drive.
What is eating your Windows 11 disk space
The culprit is a component called Capability Access Manager. It is the part of Windows that governs app permissions — which apps may use your camera, microphone, location, contacts or screen recording — and it logs every one of those permission requests to a small SQLite database. That database keeps a companion write-ahead log (WAL) file, which is supposed to be merged back into the main database periodically and shrink back to a few megabytes.
On affected machines it never gets compacted. It just keeps growing. Reports collected by Windows Latest across roughly 10,000 tracked endpoints found 59% of them carrying a WAL file over 1GB, growing by an average of 1.1GB per week, with individual machines hitting 65GB, 332GB and — in the worst publicly reported case — around 500GB. On a 512GB laptop SSD, that is the entire drive.
The trigger appears to be something on the system repeatedly polling a permission-gated capability, most commonly location. In community threads on Microsoft’s own Tech Community forum, users traced runaway growth to background apps and utilities that query location or Wi-Fi status on a loop, keeping the Capability Access Manager service (camsvc) writing continuously.
It is worth pausing on what this file actually is: a rolling record of every time an app asked to use your camera, mic or location. That log exists for a legitimate reason — it powers the privacy history you can see in Settings — but a permissions audit trail that silently balloons to hundreds of gigabytes without a single notification from Windows is a design failure, not a minor storage inconvenience.
Step 1: Check whether your PC is affected
The file lives in a system folder that is not hidden, but you will never stumble across it by accident.
- Open File Explorer and paste this into the address bar, then press Enter:
C:\ProgramData\Microsoft\Windows\CapabilityAccessManager - Look for the file named
CapabilityAccessManager.db-waland check its size in the Size column. - On a healthy system the whole folder is a couple of megabytes. If the
.db-walfile is measured in gigabytes, you have found your missing storage.
If you prefer the command line, open Command Prompt and run:
dir "C:\ProgramData\Microsoft\Windows\CapabilityAccessManager"
You can also confirm the symptom first from Settings > System > Storage, where the wasted space typically shows up lumped under system files rather than under any app or your own documents.
Step 2: Install the update that fixes it
Microsoft addressed this in the June 2026 preview update for Windows 11 24H2 and 25H2, KB5095093, with a one-line entry in the release notes added on 29 June 2026:
[Storage] This update improves disk space usage for the CapabilityAccessManager.db-wal file.
That is the entirety of Microsoft’s public acknowledgement — no known-issue dashboard entry, no advisory, for a bug capable of filling an entire system drive. Because Windows cumulative updates roll forward, the fix is also carried in the July 14 security update KB5101650 and everything released since, including the July 18 out-of-band KB5121767 patch that fixed the Dell shutdown problem.
To install it, go to Settings > Windows Update and click Check for updates. If you are on 24H2 or 25H2 and fully patched to the July updates, you already have the fix. Nothing to do beyond step 3.
Step 3: Reclaim the space the file already took
Here is the catch: the update stops the file growing further, but on many machines it does not shrink the existing monster file. Reboot and re-check the folder size first — on some systems Windows compacts it on its own within a day or two.
If it is still huge, the file cannot simply be deleted while Windows is running normally, because camsvc holds it open. The safest route is Safe Mode:
- Go to Settings > System > Recovery and under Advanced startup click Restart now.
- Choose Troubleshoot > Advanced options > Startup Settings > Restart, then press 4 to boot into Safe Mode.
- In Safe Mode, navigate to
C:\ProgramData\Microsoft\Windows\CapabilityAccessManagerand delete onlyCapabilityAccessManager.db-wal. - Restart normally. Windows recreates the file at its normal size.
Do not delete the main CapabilityAccessManager.db file, and do not disable the Capability Access Manager service. Community reports of disabling camsvc describe broken app permissions and Wi-Fi and camera access failing afterwards. The service is load-bearing.
If it starts growing again
If the file balloons a second time even after patching, something on your PC is hammering a permission check. The workaround users on Microsoft’s Tech Community landed on was to turn location polling off: go to Settings > Privacy & security > Location and switch off Location services, or at minimum Let desktop apps access your location. Treat that as a diagnostic rather than a permanent fix — if switching it off stops the growth, the offending app is one of the desktop programs in that list, and you can re-enable location once you have identified and updated or removed it.
One honest caveat: none of the reclaim steps above come from a Microsoft support article. Microsoft has published a fix but no recovery guidance, so the deletion procedure is derived from what users and Windows-focused outlets have verified on affected machines. Back up anything important before booting into Safe Mode and deleting system files, and if your drive is already so full that Windows will not boot, use the recovery environment rather than trying to force your way through a normal login.
Sources: Microsoft (KB5095093 release notes), Windows Latest, Microsoft Tech Community
