Windows Defender Update Allegedly Breaking Down sfc /scannow on Windows 10

A number of Windows 10 users are reporting that fixing corrupted files with sfc /scannow no longer works, and the culprit appears to be an update that Microsoft shipped for Windows Defender.

While initiating a scan with the Windows System File Checker built-in tool in Windows 10 seems to be working as expected, the process eventually fails with the following message displayed in the Command Prompt window used to launch it:

“Windows Resource Protection found corrupt files but was unable to fix some of them. For online repairs, details are included in the CBS log file located at windir\Logs\CBS\CBS.log. For example C:\Windows\Logs\CBS\CBS.log. For offline repairs, details are included in the log file provided by the /OFFLOGFILE flag.”

But as per BP, users posting in this discussion thread reveal that checking the said corrupted files with the fsutil hardlink list command indicates there’s nothing wrong with the hashes or the file links.

Right now, the problem appears to be linked to a recent Windows Defender update, despite the fact that it showed up just after the July 2019 Patch Tuesday updates shipped earlier this week. Windows updates are known for causing various issues, but for now, the sfc /scannow bug is experienced on devices where the latest updates aren’t yet installed too.

How to fix the problem

The buggy virus definition updates for Windows Defender could be 1.297.823.0, but a confirmation that these are causing the issues is yet to be offered by Microsoft.

Meanwhile, fixing the bug is possible with a series of DISM commands, as reported by some users who came across the sfc error. The three commands which you need to run in an elevated Command Prompt window (one by one) are the following: