Defender to automatically scan portable drives for viruses

Rather than waste your effort spitting into the wind, I'll explain what appears to be the reason that Microsoft chose not to do this with Defender.

In earlier versions of Microsoft Security Essentials the ability to automatically scan USB removable devices was configurable and as I recall, it was once included in Windows Defender as well.  However, in more recent versions of Defender it has changed to require relatively extreme workarounds like the one Dave provided above.

After dozens of such requests referencing other security software and expectations, I finally saw an explanation that made sense several months ago, though I can't provide a reference to the thread since it was so obvious when I heard it that I didn't feel the need to save a favorite to the thread.

The reason for this is that automatically scanning any removable device is dangerous, since unless the user is fully aware this is happening, they might attempt to remove the device in the middle of the scan.  Since there's no ability for the operating system to arbitrate this potential conflict it's highly likely this will result in logical damage to device data and the potential for the corruption and loss of all data the device contains, since devices like flash drives are serial communications devices and the corruption of a key section of the device's directory could destroy the index to all data it contains.

Now this scenario isn't actually that likely if an individual properly ejects and waits for the notification it's safe to remove the device, but if they simply pull it out or the scan happens to be performing a critical set of steps relating to the removal of malware or other more complex directory operations at the time the device is removed, then the chances for data loss increase exponentially.

So though on its surface this sounds like a reasonable idea, a relatively simple analysis of the potential for loss of data leads to an obvious explanation for why it was removed and is unlikely to ever return.

Rob

Hi PaulPChou,

I am Dave, an Independent Advisor, I will help you with this.

Do you want to manually scan USB drives or have Defender automatically scan a drive when it is inserted?

1

To manually scan a USB drive, go into Defender, then select Custom Scan, add the USB drive and perform the scan

2

To set Defender to automatically scan USB drives, if that is not already set.

Click your Start Button, type regedit and hit Enter to open the Registry Editor.

Click View and make sure 'Address Bar' is turned on.

Paste this into the Address Bar at the top and hit Enter.

HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender

Right click Windows Defender in the left pane and choose New - Key

Name that Scan

Select that new Key (folder)

In the right pane, right click and create a new 32-bit DWORD value

Mane that DisableRemovableDriveScanning

Double click that new key and set its Value data to 0 and click OK

Close the Registry Editor

I will try the registry one later. I want Defender to be like Norton or other third party anti-virus softwares to automatically scan. No need to go to registry. Please help me upvote my feedback.

That is why I don't like the way this is done. I want it to be like Norton or other third party software. They do a good job of scanning for portable drives, etc. Please upvote, thanks. https://aka.ms/AAcwf5o

Hi Paul,

There will be no indication that Defender is scanning the USB drives, until malware is found. Microsoft really should make this whole process easier, there should be an On/Off switch to scan external media automatically like there is in other 3rd party security suites, and a popup when you insert a USB to indicate it was scanned and no threats were found.