Windows Defender in Windows 8.1 Will Not Turn On

Anonymous
2013-11-24T01:31:23+00:00

I recently updated Windows 8 to Windows 8.1.  Windows Defender had been on in Windows 8 and even after the update to 8.1.  I turned it off momentarily but have been unable to turn it back on.  To my knowledge, I have no other anti-virus programs running.  How can I turn it back on?

Windows for home | Previous Windows versions | Security and privacy

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  1. Anonymous
    2015-09-15T11:30:21+00:00

    If you cannot resolve your problem with Windows Defender, please post follow-up (provide as much detail as possible) information/questions in the following thread dated September 11, 2015:  http://answers.microsoft.com/en-us/protect/forum/protect_defender-protect_start/error-577-when-i-try-to-start-windows-defender/c6099946-c07b-4fe1-a8f9-e08853479800

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  2. Anonymous
    2015-09-15T11:29:16+00:00

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  3. Anonymous
    2015-09-15T10:32:37+00:00

    None of the above works.  It was NEVER on in my new hp 11Aug15.

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  4. Anonymous
    2015-09-15T02:17:35+00:00

    i uninstalled Mcafee and then Window Defender automatic turned on it self.

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  5. Anonymous
    2015-09-14T20:45:20+00:00

    I have 8.1 also & it works on here but if you have another anti-virus program running also (Like MaleWareBytes) it won't run at the same time . You can only use one or the other . My Malware Bytes was actually HACKED (lol) from someone in beautiful, war-torn Afghanistan . I know because I started having pop-ups & spy ware, so I did I free SpyWare scan from Microsoft & got rid of that, but I also saw squiggly lines instead of English, so I un-installed it (even though it's paid for) grr ... and am having problems even getting in touch with CSR there. But my Windows Defender came right on. Just check to make sure you aren't running another one that is incompatible with that one. Good luck.

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