
Windows Security signatures are digital fingerprints that verify the integrity and authenticity of various software components, such as drivers and updates, to ensure they have not been tampered with. These signatures must be up-to-date to ensure your antivirus, including Microsoft Defender, effectively detects and protects against the latest malware threats. While Microsoft Defender generally updates these signatures automatically, you may need to update Windows Security signatures manually on Windows.
The situations when you are required to update Windows 10/11 Windows Security signatures manually may include troubles with Windows Update or the system missing recent security updates, the need to update your system offline, or other specific scenarios where an automatic update does not work.
However, if you need help performing manual Windows Security signature updates, this article is for you.
In this article, you are going to learn how to update Windows Defender signatures manually in the quickest and easiest ways possible. Let’s get started with them right away to save precious time.
Methods to Update Windows Security Signatures Manually Windows 10/11
You can follow any of the following methods, depending on your convenience, to update Windows 11/Windows 10 Windows Security signatures manually.
Method 1: Use the update functionality of Microsoft Defender
You can update Microsoft Defender using the built-in update tool to download and install the update for Windows Security signatures manually on Windows. While this method may not work if you are already experiencing problems with Windows Update, below is how to try it.
- First, right-click the Windows icon on the taskbar and choose Settings from the menu that appears.
- Once the Settings window appears, click on the Update & Security settings. If you are a Windows 11 user, choose Privacy & Security.
- In this step, choose Windows Security from the left panel of the on-screen window.
- Next, click Virus & Threat Protection.

- In this step, choose the option to Check for Updates from the Virus & Threat Protection Updates section.
- Wait until Windows downloads and installs the available updates.
- Lastly, restart your computer to allow the updated Windows Security signatures to take effect.
Also know: How to Activate Windows Security on Your Device
Method 2: Update Windows Security signatures manually using Windows PowerShell
You can use a unique PowerShell command to update Windows 10/Windows 11 Security signatures manually. Here is how.
- In the first step, right-click the Windows icon on the taskbar and select Windows PowerShell (Admin) from the options on your screen.
- Once the Administrator PowerShell appears, type or copy and paste the following command and then press Enter.
Update-MpSignature

- Lastly, wait for the process to complete and restart your computer after it completes.
Method 3: Update Windows Security signatures manually through the Microsoft web page
Microsoft has a webpage called “Microsoft Defender Update for Windows Operating System Installation Images,” containing three Defender environment components. These components include the platform version (signatures for a specific Windows 10/11 edition), engine version (specific anti-malware engine version), and security intelligence version (current security intelligence updates). All these versions get periodic updates that you can download and install by following the steps below.
- First, navigate to the Microsoft Defender Update for Windows Operating System Installation Images page.
- Next, click on the link to obtain the update, depending on whether you have a 32-bit, 64-bit, or ARM64 operating system.

- In this step, extract the downloaded .zip file to obtain the Defender update package (defender-dism-[x86|x64|arm].cab) and an updating tool (DefenderUpdateWinimage.ps1).
- After extracting the downloaded file, right-click on the Windows icon and select Windows PowerShell (Admin).
- Once the Windows PowerShell (Admin) appears, type or copy and paste the following command and press Enter.
PS C:\> DefenderUpdateWinImage.ps1 -WorkingDirectory <path> -ImageIndex ImageIndexNumber -Action AddUpdate -ImagePath <path_to_Os_Image> -Package
Method 4: Update Windows Security signatures manually via Microsoft Update Catalog
Another way to update Windows Security signatures manually on Windows is through the Microsoft Update Catalog. You can search the current anti-malware platform updates on the Update Catalog and then download and install these updates by following the directions below.
- First, visit the Microsoft Update Catalog.
- Next, type Microsoft Defender in the search bar on the Microsoft Update Catalog and press Enter.
- In this step, click on the Download button for the most recent update. 0

- Next, click on all links that appear on your screen to download the update file.
- You can now double-click on the downloaded files and follow the on-screen instructions to complete the manual Windows Security signature update.
Also know: How to Fix Kernel Security Check Failure Error in Windows 10,11
Windows 10/11 Windows Security Signatures Updated Manually
This is how to update Windows Security signatures manually on Windows 10/11 to protect against the latest malware and cyber threats. You can follow any method from the guide above, depending on which of these methods works best for you.
However, if you need help updating Windows Security signatures or have any feedback about this article, you can leave it in the comments section. We will be glad to address your queries and suggestions.