Windows 10: Windows Defender Antivirus wont start

Hello, I have a 4 day old new HP computer and I want to run Windows Defender. I had a free trial version of McAfee. I uninstalled McAfee using their uninstaller. Windows Defender antivirus wont start. I get a message: "unexpected error. sorry, we ran into a problem please try again."

:)

 

Defender AntiVirus

There are 4 options under Defender. Two refer to AntiVirus; AntiVirus Network Inspection Service & AntiVirus Services. Under Startup Type these two are listed as manual and the Status column said Inspection Service is running. When I clicked on the Start
button in Properties, I got an immediate message: "Win.. Def.. Anti.. Serv.. on local comp.. started and then stopped. Some services stop automatically if they are not in use by other services or programs."

 

Defender AntiVirus

Hello,

Thank you for sharing this to Microsoft Community. Let's try to start Windows Defender services and see if it helps. Follow these steps:

• Press Windows + R key and type
  
  Services.msc and press Enter.
• Search for the service "Windows Defender".
• Right click on "Windows Defender" and click Properties.
• Click Start button.
• Click Apply and Ok to save changes.
• Restart the computer and check.

Let us know how it goes.

 

Windows defender antivirus

Any other security program installed?



The behavior you are describing may
sometimes occur if another antivirus program is installed or there are remnants of a third party antivirus program still installed.



https://support.microsoft.com/en-us...b59cebc4f24/how-to-protect-your-windows-10-pc
Note the statement "If you want to use Windows Defender Antivirus, uninstall all of your other antivirus programs and Windows Defender Antivirus will automatically turn on. You may be asked to restart your device."



Go to Security and Maintenance, look in 'Security' and see what program is listed under Virus Protection. Windows Defender will not be enabled and functioning properly if there is a program other than Windows Defender listed.



See theAnswer
of quietman7 in this thread:windowsdefender wont turn on



If you cannot resolve an issue with WD, you may want to try the steps recommended in Problems
starting Windows Defender in Windows 8/8.1/10 to include (but not limited to) running SFC, scanning for malware and running the software removal tools for any security software
(AVG, Baidu, Kaspersky, McAfee, Norton, whatever) that may have previously been on the computer (to include a trial version of McAfee, Norton, etc that may have been on the computer when it was new) followed by a restart of the computer. See List of
anti-malware product removal tools





Alternatively - - -



You may prefer to install a third party antimalware program (which should disable Windows Defender).



There are a number of viable free and paid options available – take your pick…



Choosing an Anti-Virus Program



Is Windows Defender The Best For Windows
10? Good article but ignore the ads.



http://windows.microsoft.com/en-US/windows/antivirus-partners#AVtabs=win10



Regards…



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