I get an error code 0x800106b5 while trying to start Windows Defender.

Try the following: http://support.microsoft.com/kb/931849/en-us which addreesses Defender and this error code.

I hope this helps.  If not, what other security software do you have installed on your system (names and versions)?

Good luck!

---

Lorien - MCSE/MCSA/Network+/A+ --- If this post helps to resolve your issue, please click the "Mark as Answer" or "Helpful" button at the top of this message. By marking a post as Answered, or Helpful you help others find the answer faster.

Nope, i've tried everything, nothing seems to be working. When I go into services everything says Automatic and Started, Including Windows Firewall. It says it's automatic but the service status has stopped. When I press Start a pop-up comes up saying "Windows could not start the Windows Firewall on Local Computer. For more information, review the System Event Log. If this is a non-Microsoft service, contact the service vendor, and refer to service-specific error code 87."

When I go onto Windows Firewall with Advanced Security it says "Windows Firewall with Advanced Secuirty snap-in failed to load. Restart the Windows Firewall service on the computer that you are managing. Error code: 0x6D9."

Also, when I restart my computer, when I log onto my user it says Welcome for a long time (It didn't used to take so long) then it changes to a black screen for an extra 5 minutes and finally brings up my wallpaper and everything starts. But, something pops up everytime in the task bar when I turn on my laptop which I've never seen before. "Failed to connect to a windows service. Windows could not connect to the System Event Notification Service service. This problem prevents limited users from logging on to the system. As an administrative user, you can review the System Event Log for details about why the service didn't respond." But it doesn't give me an error code to try and fix.

When I go into Windows Security Center, under Security essentials the four options which include Firewall, Automatic Updating, Malware Protection and Other security settings. Everything is set as OK apart from Automatic Updating. When I try to change the settings, I click "Change Settings..." and it pops up "Install updates automatically (recommended)" so I click onto it but nothing changes.

I do not have any other software any more as I've uninstalled all the limited time ones and the ones which aren't free. But I believe everything started happening after uninstalling these programs. I used to have PC Tools: Spyware Doctor, Malwarebytes: Anti-Malware: Malwarebytes, Fake Anti-Virus 1.64, McAfee and possibly more. (I recently removed a malicious virus/fake anti-virus software.)

 

Sorry about the long paragraphs, it's a  very stressful matter and I have a lot of things wrong with my computer and it's taking me around in circles!

Did you get a resolution for this - I have the same issue with new PC - unistalled Norton and Im locked out!!!! from starting windows defender.  should be illegal.

Hi,

 

Thank you for contacting the Microsoft Community.

This thread is too old to be responded to. I would have you create a thread of your own to avoid confusion.

Refer the link-

http://answers.microsoft.com/en-us

Feel free to contact the Microsoft Community for any issues pertaining to Windows in the future. We will be happy to help.