Your Windows 11 PC might be hiding a 500GB storage bug - how to check

Lance Whitney/ZDNET

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ZDNET's cardinal takeaways

• A bug successful Windows 11 tin assertion up to 500GB of disk space.
• The culprit is simply a Windows strategy record that conscionable keeps growing.
• The bug is fixed successful the Windows June preview update and the July update.

Do you person a sneaking suspicion that your Windows PC is losing disk space? If so, it whitethorn not beryllium your imagination, astatine slightest not if your strategy has been deed by a known bug.

A peculiar record successful Windows 11 tin turn to the constituent that the nonaccomplishment successful disk abstraction becomes noticeable. The culprit present is simply a strategy record named CapabilityAccessManager.db-wal, arsenic spotted and described by Windows Latest.

Part of the Capability Access Manager Service, this different obscure record manages the permissions granted to applications to entree the camera, microphone, location, and different privacy-minded features. The db-wal hold indicates that this record stores immoderate changes successful a write-ahead log earlier they're written to the main database.

Also: You tin soon reconstruct Windows 11 from scratch adjacent if it can't footwear up - here's how

The record itself tin surely turn arsenic it needs to support way of much data. However, it should apical retired astatine nary much than a megabyte oregon two. Instead, the bug successful Windows seems to origin it to grow to arsenic overmuch arsenic 500GB, according to one Redditor who posted a connection a twelvemonth ago (yep, it's been astir astatine slightest that long).

How to archer if you're affected

How tin you archer if you're affected by this bug? One mode is to cheque the size of your Windows strategy files. 

To bash that, spell to Settings, prime System, and past click Storage. Under the archetypal barroom image, click the nexus for "Show much categories." If the class for System & reserved shows nary much than 2 oregon 3 twelve gigabytes, past you're successful the clear. But if it indicates a size that stretches beyond 100GB, past your strategy is apt affected by the bug.

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I checked each my Windows 11 environments, including those straight connected PCs and those successful virtual machines. On each but one, the size for this class ranged anyplace from 5GB to 25GB. But connected my superior Windows 11 laptop, the size deed 151GB.

Okay, but however bash you cognize that CapabilityAccessManager.db-wal is to blasted for the growth?

The record itself is housed successful the pursuing location: C:\ProgramData\Microsoft\Windows\CapabilityAccessManager. However, Windows denies you entree to that folder by default, and I don't suggest changing the permissions connected a strategy folder adjacent if you cognize how.

Instead, Windows Latest recommends moving a inferior similar WizTree, TreeSize, oregon WinDirStat successful admin mode to presumption the files successful that folder. But there's an easier enactment utilizing the built-in Robocopy tool. Open a bid punctual arsenic an head and benignant the pursuing string: robocopy "C:\ProgramData\Microsoft\Windows\CapabilityAccessManager" "%TEMP%\CAMCheck" /L /B /R:0 /W:0 /BYTES /NP.

I ran that Robocopy bid connected my ain Windows 11 installations. Almost each reported a size of astir 57,000 bytes, oregon a fraction of a megabyte. But connected my superior Windows 11 laptop, CapabilityAccessManager.db-wal weighed successful astatine 7GB, not retired of power but inactive overmuch larger than normal.

How to hole the glitch

Though the bug has been astir for astatine slightest a year, Microsoft has yet gotten astir to fixing it. In the June 23 optional preview update, a enactment says: "This update improves disk abstraction usage for the CapabilityAccessManager.db-wal file." That apt explains the quality among my PCs. I've already tally this preview update successful my Windows 11 virtual machines, but not connected my laptop.

Also: How to get escaped Windows 10 information patches until October 2027

If you privation to instal this one, conscionable caput to Settings and prime Windows Update. You should spot that the 2026-06 Preview Update is available. Just click Download & Install to drawback it. But support successful caput that these preview updates are optional for a reason. They're designed much for IT admins and powerfulness users who privation to trial them up of the wide release.

The aforesaid updates are packaged into the pursuing month's authoritative Patch Tuesday rollout, which is designed for each Windows users. If you tin unrecorded with the changeable to your disk space, I'd counsel waiting until July 14 to drawback the full mandatory update. At that point, this record size bug should beryllium squashed for everyone.