Windows 11 storage bug fix: How to check if KB5095093 applies

A Windows 11 bug has been quietly consuming storage on some machines for roughly a year, with a single background file capable of swelling from a few megabytes to as much as 500GB. Microsoft released KB5095093 as a preview optional update to address it last month, with a mandatory rollout expected through next week's Patch Tuesday, PCWorld reported yesterday.

The Windows 11 storage bug fix applies only to versions 24H2 and 25H2. The official KB5095093 support page confirms the patch covers both. If the machine isn't running one of those versions, the update won't apply.

The bug involves a file called CapabilityAccessManager.db-wal, part of the system component that manages app permissions. Under normal conditions it sits at a few megabytes. Under this bug, PCWorld reports it can balloon to several hundred gigabytes, and in the worst cases fills the drive entirely, which can significantly reduce system performance. If your PC is slow and storage seems to have disappeared, this is the file to check.

How to find the CapabilityAccessManager.db-wal file and check its size

Windows' built-in storage tools won't surface this file. Checking requires a third-party disk analysis utility. PCWorld recommends TreeSize, WinDirStat, or WizTree, all free tools that map the drive visually and let you sort by file size. Run any of them against the system drive and look for CapabilityAccessManager.db-wal in the results.

If the file is measuring several gigabytes or more, the bug is present, per PCWorld. A file in the megabyte range is normal.

Worth flagging before moving on: PCWorld warns that deleting the file outright or attempting to uninstall the Capability Access Manager could introduce additional errors. The documented fix is KB5095093. Don't try to shortcut it.

What the Windows 11 storage bug fix actually says, and what it doesn't

KB5095093 dropped June 23 as a preview cumulative update. BleepingComputer confirmed it as a legitimate update covering both 24H2 and 25H2. It's available now via Settings → Windows Update → Advanced options → Optional updates, per PCWorld. Users who wait will get it automatically through Patch Tuesday.

Microsoft's patch note on the issue is brief. The relevant line reads: "This update improves disk space usage for the CapabilityAccessManager.db-wal file," per the KB5095093 documentation. PCWorld characterizes that language as an indirect acknowledgment phrased as routine housekeeping rather than an admission that a bug has been silently consuming hundreds of gigabytes of user storage. The support note doesn't explain the root cause.

That framing also leaves something important unresolved. Describing an "improvement" to disk space usage doesn't confirm whether an already-bloated file gets trimmed down, or whether the update only stops further growth going forward. For anyone sitting on a drive that's already 200GB lighter than it should be, that's not a small distinction.

The open question: does the patch reclaim lost space?

This is where the reporting runs out. Neither Microsoft's patch note nor the sources reviewed here document a supported method for recovering storage the file has already consumed. The update may handle cleanup automatically. It may not. Microsoft hasn't said.

The only way to know is to install KB5095093 and re-run the disk analysis tool afterward. If CapabilityAccessManager.db-wal has shrunk, the patch cleaned up as well as stopped the bleeding. If the file is still large and the storage hasn't come back, there is currently no confirmed next step. That's the gap Microsoft has not yet addressed publicly, and it's the one worth watching.

It's also worth noting what the update does not answer: what causes the file to grow unchecked in the first place. The reporting reviewed here does not say what triggers the runaway growth, what conditions make some machines vulnerable and others not, or how widespread the problem actually is. A year of user reports and a one-line patch note is the full public record so far.

What to do right now

For any Windows 11 24H2 or 25H2 machine:

• Confirm the Windows version first. If the machine isn't on 24H2 or 25H2, the update won't apply.
• Use TreeSize, WinDirStat, or WizTree to locate CapabilityAccessManager.db-wal on the system drive. Several gigabytes means affected; a few megabytes means normal, per PCWorld.
• Do not delete the file or touch the Capability Access Manager component.
• Install KB5095093 now via Optional updates, or wait for the automatic Patch Tuesday rollout, per the Microsoft support page.
• After installing, re-run the disk scan. If the file is still large and the storage hasn't returned, watch for further guidance from Microsoft.

The bug has been present for roughly a year, per PCWorld. The fix is here. Whether it cleans up after itself is the one question still worth asking.