1.    07 Aug 2015 #1
    Join Date : Oct 2014
    Posts : 143
    Windows 10 1607

    Windows Defender updates failed, service won't start

    The last few days, Defender has been trying and failing to update its definitions. A manual update from Defender fails. Now Defender isn't working. Pressing Defender's Start button gives the message that the underlying service isn't running. The service is set to automatic, it can be started but immediately stops.

    Is there any known way to repair this short of a Windows refresh?
      My ComputerSystem Spec
  2.    07 Aug 2015 #2
    Join Date : Aug 2015
    Posts : 18

    Hello markweatherill:

    Some security products of other companies may intentionally disable Windows Defender to prevent mutual interference.

    Besides Windows Defender, has any other security product been installed on the system with Windows 10?

    Thank you.
      My ComputerSystem Spec
  3.    08 Aug 2015 #3

    go to the tutorial for problem getting up dates

    it worked for me, but i still need to that every other day but it works
    i'll look for it and try to send the link
      My ComputerSystem Spec
  4.    11 Aug 2015 #4
    Join Date : Oct 2014
    Posts : 143
    Windows 10 1607
    Thread Starter

    I made a Windows 10 ISO, updated Windows 10 and it 'fixed' the problem.
      My ComputerSystem Spec


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