Windows defender

Question

I dont have the options for Microsoft defender to check external harddrive connected to my laptop, windows 11.

Answer 1

Hi Terje Pedersen,

Thanks for reaching out to Microsoft Q&A Forum. I understand you don’t see an option in Microsoft Defender to scan an external hard drive connected to your Windows 11 laptop.

Please make sure you already tried the Q&A Assist steps. In addition, please try the following.

1. When you open File Explorer and right-click the external drive under This PC, do you see Scan with Microsoft Defender (sometimes under Show more options)?
2. When you use Custom scan, are you able to select the external drive letter (for example, D: or E:)?

In the meantime, you can try these steps:

1, In File Explorer, open This PC, right-click the external drive, select Show more options, then select Scan with Microsoft Defender.

2, Open Windows Security, go to Virus & threat protection, select Scan options, choose Custom scan, then select the external drive letter and start the scan.

3, If you only need the drive scanned on-demand, use Custom scan (it is intended for scanning specific locations such as a removable drive that’s currently mounted).

4, If you want removable drives to be included during Full scan, enable the Microsoft Defender Antivirus setting Scan removable drives (the related PowerShell preference is -DisableRemovableDriveScanning).

5, If Real-time protection is enabled, files on mounted removable media (such as USB drives) are included in the scanning scope when accessed, so try opening a folder on the external drive and re-run a Custom scan targeting that drive/folder.

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Answer 2

Open Defender.

Select Custom Scan.

Select either the Quick or Full scan option.

On the next window, do you see the option to select which folders/drive to scan?

If not, do you have any 3rd party anti-virus installed on your PC.

Answer 3

If you are unable to find the options for Microsoft Defender to check an external hard drive on your Windows 11 laptop, it may be due to the settings configured in your system. You can manage whether or not to scan removable drives by adjusting the policy settings for Microsoft Defender Antivirus.

To enable scanning for removable drives, you can use Group Policy or other management tools like Microsoft Intune or Microsoft Configuration Manager. Specifically, you can look for the policy setting Scan_DisableRemovableDriveScanning which controls whether removable drives are scanned during a full scan. If this setting is disabled or not configured, removable drives may not be scanned.

To check or modify this setting:

1. Open the Group Policy Management Console.
2. Navigate to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus > Scan.
3. Look for the Scan_DisableRemovableDriveScanning policy and adjust it as needed.

Make sure your Microsoft Defender Antivirus is up to date and configured correctly to ensure it scans all connected drives, including external ones.