Windows 10: Windows defender is missing from registry and services. How do I reinstall it?

My windows defender is somehow missing from services and registry. When I try open windows security, I am stuck on a blank screen. How do I reinstall or get windows defender working again?

:)

 

How reinstall windows defender

Hello LucianN1, my name is Irisdiel and I am an independent advisor.

I suggest you follow the instructions down below.

Step 1: Enable Windows defender from control panel

1. Press Windows + X, Click on control panel.

2. On right top corner click on View and then choose large items.

3. Now from the list click on Windows Defender and try to enable it.

If not try to enable it from services.

Step 2: Enable Window defender from services.msc.

1. Press Windows + R, to open run prompt.

2. Type services.msc and press enter to open services list.

3. Under services look from Windows defender service and start the service.

I also suggest you refer to the link down below.

URL:
https://answers.microsoft.com/en-us/protect/for...

Hope this helps!

Thank you and good luck,

Regards- .

 

Windows Defender Error 1058: can't start service

I've seen posts regarding similar behavior for Windows 7, but not for Windows 10. I've tried a few of the steps but some of them (like specific registry key updates) are not applicable, since the registry seems different than previous versions.

Symptoms

• Windows Defender always fails to start, gives "Error 1058"
• Under Settings > Update & Security > Windows Defender, every option is greyed out
• Can't manually start the "Security Center" service
  • Initially set to "Disabled"
  • Change setting to "Automatic," start service manually
  • After a short time, it reverts back to "Disabled"

Troubleshooting Steps

• Performed virus/malware removal
  • Malwarebytes, SUPERAntiSpyware, HitmanPro, AdwCleaner, Kaspersky's TDSS Removal, Bitdefender, Spybot
  • Individually installed, scanned, and removed each
  • Found some adware/viruses that were removed
  • Nothing shows up in any scans now (seems like everything active was removed)
• Checked Group Policy Editor/registry key for the "Disable Windows Defender" setting
  • Made sure everything was set to "enable" Defender
  • Still see symptoms
• sfc /scannow
  • Showed some errors that couldn't be resolved
  • Seems to be missing critical files in the running and backup file list
  • I have the CBS.log that was ran immediately before posting; not sure how to attach it or if I should include a snippet
  • EDIT: just re-looked through the log output, seems like most of the "check failed" errors were for different shortcut files (Task Scheduler, etc.). Not sure how applicable this is now

Possible Solutions

• Download + reinstall Windows Defender to replace missing files
  • Not sure if this is even possible, given that it's a core system component in W10
• Restore Registry keys back to default settings
  • Virus seems to have messed up several places
  • Nothing specific to Windows 10 online for getting Windows Defender back to stock in registry

 

windows defender & security center services keep turning off


Are you running any other AV or did you have one running in the past? If you didn't use an uninstaller for the AV, then the remnants of it could be causing the problem. Normally any time you install an AV it disables Defender by default.

If you are getting any error codes please list those, that will be helpful in helping you.

As torre suggested, might be a good idea to do a reset or even a reinstall.

Reset Windows 10 - Windows 10 Forums

Windows 10 - Clean Install - Windows 10 Forums

There are also some suggestions listed here:

Unable to turn on Windows Defender in Windows 7 / 8 / 10