Windows 11 Bug That Can Exhaust Your System Drive with 513 GB Log Files

Microsoft has acknowledged a new issue in Windows 11 24H2/25H2 where the Capability Access Manager (CAM) service generates an ever‑growing log database. Under normal conditions the CAM database is only a few megabytes, but the bug can cause the .db‑wal file to expand to 70 GB–200 GB, with extreme cases reaching 513 GB, quickly consuming the entire system‑drive space.

The oversized log file is located at

C:\ProgramData\Microsoft\Windows\CapabilityAccessManager\CapabilityAccessManager.db‑wal

. Users can notice abnormal growth in the "System and Reserved" category of the Storage settings.

To determine whether a machine is affected, open Settings → System → Storage → Local Disk → Show more categories → System and Reserved. If the size appears unusually large, run the following command in an elevated command prompt to copy the CAM folder and inspect the log size (the folder is otherwise permission‑locked):

robocopy "C:\ProgramData\Microsoft\Windows\CapabilityAccessManager" "%TEMP%\CAMCheck" /L /B /R:0 /W:0 /NP

On a test machine without the bug the log file is only 1.41 MB. If the command reports a size in gigabytes, the system is impacted. Deleting the file is not recommended; instead, install the preview update KB5095093, which Microsoft says improves CAM file disk‑space usage. The update will be rolled out to all users in the next B‑channel stable release, and affected users can install the preview early via Windows Update.

After applying the update and restarting, the CAM database should shrink back to its normal size automatically. Although some users consider disabling the Capability Access Manager Service to stop the growth, doing so can break network connectivity or prevent login, so it is not advised.