Microsoft Security Essentials shows more than 44,000,000 files on full scan RRS feed

  • Question

  • I ran MSE with full scan on a Dell 570 desktop with Windows 10. After three days and nights the file count was 44 million and still going up. I downloaded Foldersizes software and it showed no folder with millions of files on C drive. System properties doesn't show Windows and subdirectories as having that many.  Not sure if MSE scans attached USB drives, of which there are several.  I ran disk check from C properties tools, and it reported no errors on C.  I was wondering about possible index corruption leading to recursion in the file structure, but it doesn't seem to show up anywhere else than MSE.

    It would be nice to do a full scan using MSE.  The program reported that there were possible problems, but it didn't finish (I canceled it after three days), so I don't know what they were.

    Any suggestions would be appreciated.


    Tuesday, July 18, 2017 5:48 PM

All replies

  • I mean Windows Defender, not MSE.  If the full scan includes attached USB and network drives, there could be several million files, but 44 million sounds like a lot.


    Tuesday, July 18, 2017 6:13 PM
  • if you in a PowerShell prompt you run;


    That has two settings, DisableRemovableDriveScanning & DisableScanningMappedNetworkDrivesForFullScan both set to True to my default system. Check those.

    • Edited by -Mr Happy- Tuesday, July 18, 2017 9:53 PM correction
    Tuesday, July 18, 2017 9:41 PM
  • Am currently running a custom scan with only drive C selected.  I will let it run all night.  So far after 5 hours it is about 40% done, but in the earlier try it slowed down later.  If it runs to completion by tomorrow morning, that would be good.  Otherwise I will cancel it.


    Wednesday, July 19, 2017 12:08 AM
  • Scan froze after about 4,000,000 items.  Elapsed time no longer updated.  I canceled the scan.  This work on Defender is a career that I don't want to pursue, so maybe I'll get a different anti-virus.  Thanks to all.


    Wednesday, July 19, 2017 6:24 AM
  • According to your description, all things looks normal, I don’t find something strange.

    Full scan obviously means scan all of your drives, including HDD disks and external drives, if you ever enable scan mapped network drives via PowerShell command or GPO, Windows Defender will also scan mapped drives, there are many files on network drives and will cost lots of times.

    You could run this command below in an elevated PowerShell to disable Scan Mapped Network Drives during Full Scan.

    Set-MpPreference -DisableScanningMappedNetworkDrivesForFullScan 1

    You could open group policy editor to manage Windows Defender’s scan function.

    Computer Configuration/Administrative Templates/Windows Components/Windows Defender/Scan


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    Wednesday, July 19, 2017 6:49 AM
  • Would you mind letting me know the update of the problem? If you need further assistance, feel free to let me know. I will be more than happy to be of assistance.

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    Wednesday, July 26, 2017 6:55 AM