How to Fix Windows Defender when it Fails to Turn On



Here's How:
1. Right-click Command Prompt and Run as Administrator. Type the following command:

winmgmt /verifyrepository
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2. If the system returns "WMI repository is not consistent", run this command:
NOTE: The first time you run this it will fail. (It will issue stop commands to the services causing it to fail. It might take a couple minutes for the
services to shut down). Run the command again. You actually may have to run it 3 times before it finally runs and completes on its own.

winmgmt /salvagerepository
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3. Reboot your system.

4. If the above steps does not work please try the steps below :
A) Right-click Command Prompt and Run as Administrator. Type the following command:
B) net stop winmgmt
C) Press Y and press ENTER to continue
D) cd %windir%\system32\wbem
E) ren repository repository.old
F) net start winmgmt

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