Windows Defender doesn’t work after I install Microsoft Security Essentials

Beth writes:

“I could not get my Windows Defender to work after installing Microsoft Security Essentials. Why?”

Windows 7 and Windows Vista both come with antispyware software called Windows Defender. If you want to protect your computer from more than spyware, you can install Microsoft Security Essentials for free.

Download Microsoft Security Essentials.

Because you don’t need both programs, when you install Microsoft Security Essentials it will automatically disable (but not uninstall) Windows Defender. For more information, see Do I need both Microsoft Security Essentials and another antivirus software program?

Need security for your business?

Microsoft Security Essentials is available for small businesses with up to 10 PCs. If your business has more than 10 PCs, you can protect your computers with Microsoft Forefront Endpoint Protection.

About the Author
Eve Blakemore

Group Manager, Trustworthy Computing

Eve Blakemore is a Group Manager for Trustworthy Computing who delivers consumer guidance around the latest trends in security and privacy. Eve joined Microsoft in 1998 and has worked in corporate and field roles with Microsoft Learning, US Public Sector, Read more »

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11 comments
  1. Anonymous

    very nice product Microsoft Security Essentials secure my computer scan all type viruses.

  2. Anonymous

    Not able to access programs that load at start up because Windows Defender has been disabled since installing MSE.  

  3. Anonymous

    I would just like to say that since I downloaded Microsoft Security Essentials my PC has been working great. I've never had any problems at all. Especially after 5 years of paying someone to put an Anti-Virus Programme through my PC. I'm so glad that a friend put me onto MSE.  :-)

  4. Anonymous

    pop up blocker?

  5. Anonymous

    I can't turn windows firewall on after installing essentials.

  6. Anonymous

    I HAVE A G62 HP NOTEBOOK OS64 WINDOWSDEFENDER WILL NOT START. I HAVE TRIED EVERYTHING. PLEASE HELP ME

  7. Anonymous

    why does my microsoft security essentials turn off every time i shut my computer down.

  8. Anonymous

    I use MSE with no problems. I wish it had auto updates.

  9. Anonymous

    unable to uninstall windows defender —  I have security essentials —  I keep

    getting popup windows that windows defender is turned off  — annoying

  10. Anonymous

    No complications.. no slowness.. it is a great application and secure my system very effectively.

  11. Anonymous

    useful article and good product !

Comments are closed.