If you’ve set up a mapped network drive on Windows 10, Windows Defender won’t scan it for viruses or malware by default during its scheduled scans. Here’s how to ensure your network drives are scanned.
Home Users: Enable Mapped Network Drive Scanning via the Registry
If you have Windows 10 Home, you’ll have to edit the Windows Registry—or use PowerShell, which we’ll cover later—to make this change. You can also do it this way if you have Windows 10 Professional or Enterprise but just feel more comfortable working in the Registry as opposed to Group Policy Editor. (If you have Windows 10 Pro or Enterprise, however, we recommend using the easier Group Policy Editor, as described in the next section.)
Here’s our standard warning: Registry Editor is a powerful tool, and misusing it can render your system unstable or even inoperable. This is a pretty simple hack, and as long as you stick to the instructions, you shouldn’t have any problems. That said, if you’ve never worked with it before, consider reading about how to use the Registry Editor before you get started. And, definitely back up the Registry (and your computer!) before making changes.
You should also make a System Restore point before continuing. Windows will probably do this automatically when you install an update, but it couldn’t hurt to make one manually—that way, if something goes wrong, you can always roll back.
When you’re ready, open the Registry Editor by pressing Windows+R on your keyboard, typing “regedit” into the box, and then pressing Enter.
Navigate to the following key in the left sidebar:
If you don’t see a “Scan” key (folder) below the Windows Defender folder, right-click the Windows Defender folder and select New > Key. Name it “Scan”.
Right-click the “Scan” key (folder) in the left pane and select New > DWORD (32-bit) Value.
Name the value “DisableScanningMappedNetworkDrivesForFullScan”. Double-click it and set the Value data to “0”.
You can now close the Registry Editor and restart your computer to apply the settings to Windows Defender.
Download Our One-Click Registry Hack
Rather than editing the registry yourself, you can download our Enable Mapped Network Drive Scan registry hack. Just open the downloaded ZIP file, double-click the “EnableMappedNetworkDriveScan.reg” file, and agree to add the information to your registry. We’ve also included a “DisableMappedNetworkDriveScan.reg” if you’d like to disable it again.
These REG files just change the same registry setting we outlined above. If you’d like to see what this or any other REG file will do before you run it, you can right-click the file .reg and select “Edit” to open it in Notepad. You can easily make your own Registry hacks.
Home Users: Enable Mapped Network Drive Scanning via PowerShell
If you don’t feel comfortable editing keys in the Windows Registry, you can enable the option to scan network drives with PowerShell instead. There’s less risk using PowerShell, and you won’t have to worry about potentially messing with critical system settings. Just copy/paste the premade cmdlets we’ve prepared for this guide.
Start by opening an elevated instance of PowerShell. To do so, click the Start button, and then type “Powershell”. Right-click “Windows PowerShell,” and then select “Run as Administrator” from the menu.
Click “Yes” in the prompt that appears to allow access to your computer.
In the PowerShell window, type the following cmdlet:
Set-MpPreference -DisableScanningMappedNetworkDrivesForFullScan 0
Press Enter to run the command. The PowerShell console won’t confirm the option is set, but you can check it yourself. Type in the following command, look for the value “DisableScanningMappedNetworkDrivesForFullScan” and make sure it’s set to “False.”
If you want to disable the mapped network drive scan again, retype the command but put a “1” instead of a “0” before pressing the enter key.
You can now close PowerShell safely.
Pro and Enterprise Users: Enable Mapped Network Drive Scan via Group Policy
If you’re using Windows 10 Professional or Enterprise, the easiest way to enable the mapped network drive scan is by using the Local Group Policy Editor. It’s a pretty powerful tool, so if you’ve never used it before, it’s worth taking some time to learn what it can do. Also, if you’re on a company network, do everyone a favor and check with your admin first. If your work computer is part of a domain, it’s also likely that it’s part of a domain group policy that will supersede the local group policy, anyway.
You should also make a System Restore point before continuing. Windows will probably do this automatically when you install the Anniversary Update. Still, it couldn’t hurt to make one manually—that way, if something goes wrong, you can always roll back.
First, launch the group policy editor by pressing Windows+R, typing “gpedit.msc” into the box and pressing the Enter key.
Navigate to Computer Configuration > Administrative Templates > Windows Components > Windows Defender Antivirus > Scan.
Update: According to a commenter, you might instead have to navigate to Computer Configuration > Administrative Templates > Windows Components > Microsoft Defender Antivirus > Scan depending on which version of Windows 10 is running on your machine.
Locate the “Run full scan on mapped network drives” setting in the right-hand pane and double-click on it.
Set “Run full scan on mapped network drives” to “Enabled” and click “OK” to save the changes.
All changes have been saved and will take effect immediately. You can now close the group policy editor, and there is no need to restart your PC.
To disable mapped network drive scans, return here, double-click the “Run full scan on mapped network drives” setting, and change it to “Not configured” or “Disabled”.