Microsoft Defender questions & answers

Windows Defender is a powerful and easy-to-use anti-malware tool
Question by Guest #114267125
August 15, 2022
Answer by Saumya Sharma

The answer to the question is that Microsoft Defender does not require a registration key.

Question by Guest #42076495
May 21, 2016
Answer by Sean Hill

The updates for Windows Defender are delivered through Windows Update. I didn't see any update that can be downloaded manually, which I believe this happens due to security reasons.

Make sure that your Windows Update is working normally, then search manually for updates. If there are any, it will be downloaded for your software.

Use the troubleshooting page to diagnose and fix possible Windows Update errors:

Guest #31215202
Question by Guest #31215202
March 22, 2014

For what is Windows Defender?

Answer by Dan Angel

Windows Defender is a free of charge security program developed by Microsoft that helps you protect your system and your data against spyware and other malicious applications. You can read more about its functions on Software Informer review page of the product. Also, on Microsoft Support page you can find a user guide for the program.

Guest #27208091
Question by Guest #27208091
April 29, 2013
Answer by Guest

You use any other Anti Virus of your choice.

I would recommend MSSE. It is best for all XP, 7, 8, Vista..

You can not actually uninstall defender, however can disable it.
In Windows XP you could uninstall Windows Defender because it considers it as application that you could install but in Windows Vista and Windows 7 it is part of Windows and you could NOT unistall it. However, you could disable it.

If you are using XP, just uninstall from Add Remove program, or else use Windows® Defender Uninstaller Tool 1.0.

Although you can't uninstall Windows Defender from Vista or Windows 7, you can turn it off. To do so, click Start, type defender, and click Windows Defender. Click the Tools icon at the top of the window, then the Options link.

The rest of the instructions vary with your version of Windows:

Vista: Uncheck Automatically scan my computer (recommended), then scroll down and uncheck Use real-time protection. Click the Save button.

Windows 7: Click Automatic scanning in left pane. Uncheck Automatically scan my computer (recommended). Click Real-time protection in the left pane. Uncheck Use real-time protection (recommended). Click the Save button.

For Vista:

  1. Click Windows Start button, Type MSCONFIG in the Start Search box and Press the Enter key

  1. Click Startup tab, Scroll down and UnCheck Windows Defender Startup Item. Click OK to Save config change

  1. No need to reboot, Click Exist without restart

Additional Information (on next boot):

Windows Vista monitors the use of MSCONFIG. After you reboot and login, Vista will prompt you with a box explaining that you recently made a change and explaining how to back-out the changes if desired. Below is my recommended response to this Vista System Configuration Prompt.

  1. Check box Don’t show this message or start System Configuration when Windows starts and Click OK.

All Done..

September 27, 2008

I want to uninstall Windows Defender. Can you help?

Answer by ComputerJy

If you're using Windows XP then go to the "Add/Remove programs" in the Control Panel and click on the remove button right next to the Windows Defender. If you're using Windows Vista, then go to the Control Panel=>Programs And Features. Scroll down to Windows Defender and click the Uninstall button

Question by Guest
March 7, 2009

In my notebook, Windows Defender always shows: "Application failed to initialize: 0*800106ba. To start the service restart the computer or search help and Support on how to start a service manually". What can I do?

Answer by Bethrezen

Friend, you can start services mannually using the services console. To use it, do as follows: Click start menu then Run. Then type: "services.msc" and click "OK". On this new screen, you need to find the service you want to start. To start it, right click the service and choose "start". If u can't select the "start" option, click "properties" and search this screen for the field "initialization type", select automatic it and then click the "Start" button. Hope i could help;

Question by Duane Maurer
October 16, 2010

My Windows Defender worked fine until I downloaded & ran Microsoft Essentials. Can or should I use/install these programs together?

Stephen Prastman
Answer by Stephen Prastman

Yes, the programs are compatible one with another because these are released from the same developer as there have been no reports for compatibility issues.

Answer by Pete Clapp

Instead of Disabled or Manual set your Windows Defender to Automatic. Go to Start and type services in the Search programs and files box. Open the application, double click on Windows Defender and press Automatic in the Startup type box. Click OK and reboot your computer. If the problem persist, reinstall Windows Defender. Press the Windows+R key combination and type appwiz.cpl. Press Enter, select Windows Defender and click Remove. Install again the application and reboot the computer. For more details you can check the Microsoft Support.

Question by Guest
September 17, 2009
Answer by Rich 7

To start Windows Defender manually go to: Start icon (Bottom left) ,Then: Control Panel, Then In the left Colum be sure you are in: Classic View, scroll to Windows Defender Icon or link and click it.
At the very top Click on: Tools
Then click Options To configure and to Start the program!

June 28, 2008

I keep getting a message saying: "Unable to install". It states that "SPBBC" is missing. I can't even go to Windows Update. XP Security Center tells me "Certificates are not valid". What can I do?

Answer by marcochaos

This Version of Defender is for VISTA, not for XP ...

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