Windows 8 and 8.1 Forums


Defender will not run

  1. #1


    Ohio
    Posts : 473
    Windows 8 Pro

    Defender will not run


    I have windows 8.1 and Windows Defender will not start. If I open defender and try to start nothing happens. I go to services and try to set it to automatic, but automatic is grayed out. If while in services, I click on Start it starts and the immediately shuts down. The only other antivirus program I have installed is Malwarebytes Pro. But I even temporarily disable it, but still can't start Defender. When I open Defender and want to click on Update, it is completely frozen and nothing happens. I thought I could uninstall it in Control Panel, but it's not listed there. Since I do have Malwarebytes Pro which is a good malware program, I'm not going to worry about it too much. But there should be a way to get it running.

      My System SpecsSystem Spec

  2. #2


    Posts : 375
    Win 8.1 64bit


    Have you scanned with MB for possible malware ?

    I am not familiar with MB Pro, does it have a firewall and disable Defender ? Is it compatible with 8.1 ? Did they both run ok before, or did you just recently install MB ?
      My System SpecsSystem Spec

  3. #3


    Ohio
    Posts : 473
    Windows 8 Pro


    Thinking that there may have been a conflict with Malwarebytes, I actually uninstalled MB, but I still have the same problem. I'm not sure but I think it may have started when I installed 8.1
      My System SpecsSystem Spec

  4. #4


    Ohio
    Posts : 473
    Windows 8 Pro


    I forgot to mention that I did run a scan with MB but it found no problems.
      My System SpecsSystem Spec

  5. #5


    Posts : 2,627
    win8.1.1 enterprise


    I thought I could uninstall it in Control Panel, but it's not listed there.
    did you check services ,its listed there,2 services ,maybe set to disabled
      My System SpecsSystem Spec

  6. #6


    Posts : 375
    Win 8.1 64bit


    Personally, I would recommend a System Refresh. Files will be retained and most, if not all, apps.

    Not good when a main Windows component (Defender) is not working properly.
      My System SpecsSystem Spec

  7. #7


    Ohio
    Posts : 473
    Windows 8 Pro


    I tried to do a refresh but got a message that said, "The drive where Windows is installed is locked. Unlock the drive and try again." So now what--do I have a bigger problem?
      My System SpecsSystem Spec

  8. #8


    Posts : 375
    Win 8.1 64bit


    Restart your computer and see if message is still there.

    Also, go to PC settings and select Advanced Startup. It will take you to an option to try to repair your computer.


    I have seen this discussed before but can't recall the exact fix. Also, go to the Performance and Maintenance Forum on this site and start a thread about system being locked. Many knowledgeable posters there, moreso than I.
    Last edited by torre; 27 Oct 2013 at 16:37.
      My System SpecsSystem Spec

  9. #9


    Ohio
    Posts : 473
    Windows 8 Pro


    I restored the PC to original factory settings after I backed up my data. I then reinstalled Win8 and it's OK now.
      My System SpecsSystem Spec

  10. #10


    Posts : 375
    Win 8.1 64bit


    Good to hear !
      My System SpecsSystem Spec

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