Solved! Windows Defender will not turn on (Error 577)

[Midia_]

EDIT: Found the solution, just a little mistake.
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I'm getting Error 577 when attempting to manually start Windows Defender: https/i.imgur.com/OaEfyPu.png

Only Anti-virus related software I have is Malwarebytes and SUPERAntiSpyware (both are Free editions, no real-time protection). Never had anything other than those two.

I'VE TRIED:

• 
  * Uninstalling MBAM & SAS (even though they've never conflicted)
  * Launching it through Services and Update & Security (https/i.imgur.com/OaEfyPu.png)
  * Looking for DisableAntivirus or AntiSpyware in the registry (they don't exist http/i.imgur.com/SzWt9NU.png)
  * Restarting Security Center in Services (I can't, Start/Stop/Restart all grayed out)
  * sfc /scannow (Windows Resource Protection did not find any integrity violations)
  * Updating Defender in Security Center (Error code -2147416390: can't because service is stopped)
  * Googling, googling, googling...
  * Turning PC off and on again

I had Defender turned off for ~a year and wanted to start using it again sometime after the Creator's update... but nope.

It says Defender's client version is 4.11.15063.0 (outdated, can't update). I have Windows 10 Home x64 up to date (15063.296).

 

[Midia_]

I found the answer... I was looking at the wrong registry entry. My bad, the solution was to change value of DisableAntivirus to 0