Microsoft has released an optional Windows 11 update aimed at a very dumb storage problem: a default permissions-related file that, for some users, grew large enough to eat serious chunks of a PC’s drive.
The fix is included in Microsoft’s June 2026 optional update, KB5095093. In its support notes, Microsoft says the update “improves disk space usage” for the CapabilityAccessManager.db-wal file. That is the company’s entire public explanation, which is not exactly a root-cause analysis.
CapabilityAccessManager.db-wal is installed by default on Windows 11 machines and is tied to app permissions. The “wal” suffix usually points to a write-ahead log, the kind of file software uses while recording database changes, but Microsoft’s note does not spell out the internals here. The relevant part for users is blunter: the file was not staying reasonably sized on some systems.
Windows Latest reported the fix earlier and pointed to user complaints from the past few months. One Reddit user said the file had reached 500GB on their machine. Other users reported sizes including 12GB and 200GB, according to posts on Reddit and Microsoft’s Answers forum.
Microsoft has not said what triggered the growth. Windows Latest suggested the file may have been expanding because Windows 11 repeatedly logged access requests or privacy-control activity, including location-related events. That is a plausible-sounding explanation, but it remains an outside read of the behavior, not a confirmed diagnosis from Microsoft.
How to get the fix
Because KB5095093 is an optional update, Windows 11 users may need to request it manually rather than wait for normal automatic patching.
- Open Settings.
- Go to Windows Update.
- Select Advanced options.
- Choose Check for optional updates.
- Select and install the June 2026 update if it appears.
Microsoft describes the release as a preview update, so cautious users may prefer to wait until the fix rolls into the regular update channel. Users already watching their C drive vanish into a permissions log have a more practical reason to install it now.
The episode is another reminder that “system files” are not magic. They are files, they live on finite disks, and when logging or database housekeeping goes sideways, users get to discover the problem through missing storage space rather than a helpful Windows warning.
This story draws on original reporting from The Verge.
