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Adding "Scan with Windows Defender" to the Windows 8 context menu

Adding “Scan with Windows Defender” to the Windows 8 Context Menu

Windows 8.1 Start Screen

Windows Defender is Microsoft’s flagship antivirus program baked right into Windows 8 and Windows 8.1.  If you’re dubious about how well Defender actually defends PCs against viruses, think again.

According to a study by a German independent research team at AV-Test.org, Windows Defender catches a little more than 80% of zero-day threats.

Zero-day attacks exploit unknown vulnerabilities; the attacks occur on the same day the vulnerability becomes known to the public; therefore, the developers had zero days to deal with the vulnerability.

And although Windows Defender isn’t quite as good as AVG Antivirus Free or Avast Free, Defender still holds its own.  For example, when tested against 0-day malware attacks it pulled in a score of 81 which is only 14 points shy of the industry average of 95.  In addition, when AV-Test.org subjected Defender to a rigorous test of over 18,000 samples to see how well it discovered common viruses, Defender tied the industry average of 99.  You should read the full report from AV-test to see for yourself.

All this is great news, but to my disappointment neither Windows 8 nor Windows 8.1 comes with an option to right click a file and choose “Scan with Windows Defender”.  I think Microsoft reasoned that since Windows Defender offers Real-time Protection, there’s no need to scan on demand because Defender is already constantly monitoring the system for viruses and spyware.  And I generally agree with this rationale, but it’s helps me sleep at night to know that I can right click any file or folder and instantly scan only that file or folder with Defender.  I like precision.

If you want to know how to do this read on, I’ll get you going in less than 5 minutes.

Windows 8.1 Start Screen

Here we are at the Windows 8.1 Start Screen.  I used Windows 8.1 for my test here but these settings are also 100% compatible with Windows 8 so don’t fret if you’re not running Windows 8.1, most people aren’t yet since it won’t officially launch until October 18th.

Getting Started

The first thing we need to do is pop open the Registry Editor.

If you just felt a tremor ripple down your spine don’t be alarmed.  Yes, the Registry Editor is crucial to Windows and one mistake could render your operating system unusable but like anything important you should always have a backup.  So just as you would normally backup your photos, documents and music we’re going to backup the Registry too.

Let’s open Regedit.  Type this at the Start Screen


Windows 8.1 Start Screen Registry Search

Immediately after clicking Regedit, you’ll see a User Account Control (UAC) interactive prompt appear.  UAC is meant to improve the security of Windows by restricting applications to standard user privileges until someone with Administrator rights explicitly approves the elevation request.  Since we know we clicked Regedit (and not some malignant virus) we can confidently click Yes.

Windows 8.1 Start Screen Registry User Access Control Interactive Prompt

And now the Registry is standing before you in all its shining glory.  Okay, I’m being dramatic — but seriously, isn’t it a beauty to look at?  Okay geez, I don’t know what’s wrong with me.  I digress, anyway before we touch anything here we need to make a backup.

Go to File > Export and save the registry as full-registry-backup.

Now, if you happen to delete a crucial Registry key you can restore the entire registry by importing this backup from the File menu.

Windows 8.1 Registry Backup

Okay now let’s create the keys

Creating the Registry Keys

Navigate to:


Then right click shell, mouse over New and choose Key in the fly out menu.

Windows 8.1 Registry Adding the Keys

We’re going to create a new Windows Defender key and then make these two string values:

  1. Icon
  2. Right-click menu text

The first value will put the little Windows Defender icon in the context menu; it’s purely for aesthetics.

The second value will create the text “Scan with Windows Defender” so when you right a file or folder you can easily scan your stuff right there on the spot.

Finally, we’ll create one last key which is the actual command that launches Windows Defender and starts the scan.

I’ll walk you through the entire thing… it’s not as convoluted as it sounds.

Let’s do this.

After right-clicking shell and creating a new key name it:


Windows 8.1 Registry

Now we need to create the icon and right click menu text.  Make sure windowsdefender is still selected in the left pane, then right click in the white space of the right pane and choose New > String Value like so:

Windows 8.1 Registry Adding the new String Value

Name it Icon then double click it and add this value data:

%ProgramFiles%\\Windows Defender\\EppManifest.dll

Windows 8.1 Registry Adding the new String Text

Now, right click and create another String value named MUIVerb.  Double-click it and give it this string value:

Scan with Windows Defender

Of if you’re feeling particularly jovial you could name it anything you want like, I don’t know:

Yo, scan my files now!

My point is you could put virtually anything as the text, so please make sure you have fun with that.

Tip: It also makes for instant geek points when your friends visit and use your laptop.

Hey man, how did you do that?

Don’t tell them just smile, then refer them to fixedbyvonnie.com for more tips.

Windows 8.1 Registry Adding the new String

Now we need to add the key that contains that command to initiate the Windows Defender scan.

Right click the windowsdefender key you created earlier then click to New > Key.

Windows 8.1 Registry Adding the new Key

Name it Command then double click (Default) in the right pane and put in this value.

“C:\Program Files\Windows Defender\MpCmdRun.exe” -scan -scantype 3 -SignatureUpdate -file %1

Fun with the Windows 8.1 Registry

And now you’re done.

That’s it.

Let’s see the result of your hard work.

The Result

Open My Computer (Ctrl + e) and right click a file or folder.  You should see a new option to Scan with Windows Defender (or whatever you called it)  in the context menu.  If not, go back and double check that you entered everything exactly as delineated above.

Windows 8.1 Scan with Windows Defender in Context Menu

When you launch the scan, a toast notification appears in the upper right corner and a black command prompt flashes onto the screen.  If the item checks out okay, the black command prompt will flash and disappear in the same second.   That means Windows Defender didn’t detect any viruses or malware.

But I’m not so fortunate.  My hapless computer actually has malware… but thankfully Windows Defender detected it: eicar.com

Windows 8.1 Windows Defender Virus Found!

Windows Defender begins cleaning the threat…

Windows 8.1 Windows Defender Cleaning the Virus

And completely expunges it.

Virus cleaned!

Windows 8.1 Windows Defender Virus Cleaned


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Posted in How To, Windows 8, Windows 8.1 Tagged with:
  • serhio vilares

    not bad, but works only for folders, not for individual files…

    • Ah, I guess it isn’t perfect

      • TekWarrior

        Works great, I made both, and one says “Scan the file already will ya!!” and the other says folder instead…

        Thanks for the info =D

    • front360

      Works for files too, create all the same registry keys in HKEY_CLASSES_ROOT*shellWindowsDefender

  • Devin Johnson

    So when I try to run it, it’s telling me that I might not have the right permissions. I’ve triple checked the paths, and I’m the Administrator, so…

    • Locket

      Remove the quotation marks so it’s : C:Program FilesWindows DefenderMpCmdRun.exe -scan -scantype 3 -SignatureUpdate -file %1

      This worked for me!

      • Devin Johnson

        That was it. Thanks so much!

  • Khalid

    Yaaho….thankx this work…… and also locket thankx

  • Scott Hargrove

    Anybody have a clue how to do this in Spanish? It’s just the command key that’s causing me grief. The rest works fine.

    • Scott Hargrove

      Nevermind… it was the quotation marks. Works great.

  • Evil Otaku

    This is working fine for scanning folders. but whenever I try to scan a file, I get an error. I’ve included a picture of it. Can anyone help me out?

  • Pingback: How to scan a specific file with Windows Defender in Windows 8.1 - fixedByVonnie()

  • Melting Granite

    I do this change of registry and follow instructions exactly. Now my car do not start, and my coffee maker do not keep coffee hot. PLESSE I beg of your help how I can undo registry for make car and coffee maker work now!!!!!????