What Prevents Windows Defender from Turning On?
After receiving numerous reports from multiple users we decided to investigate the issue and devised a set of solutions that fixed the issue for most of our users. Also, we looked into the reasons due to which this error is triggered and listed them below. Now that you have a basic understanding of the nature of the problem, we will move on towards the solutions. Make sure to implement these in the specific order in which they are provided to avoid any conflicts.
Solution 1: SFC Scan
An SFC scan checks the whole computer for any missing/corrupted drivers and registry files. After checking, it automatically prompts Windows to replace them. Therefore, in this step, we will be initiating an SFC scan. For that:
Solution 2: Enabling Through Group Policy
If the Windows Defender has been disabled through the Group Policy you will not be able to turn it on unless it is re-enabled. Therefore, in this step, we will be enabling the Windows Defender from the group policy. For that:
Solution 3: Enabling Windows Defender Service
It is possible that the Windows Defender Service might be configured to be started manually after startup. Therefore, in this step, we will be enabling Windows Defender Service from the “Services” menu. For that:
Solution 4: Checking for Updates
In some cases, the Windows Defender’s definitions might be outdated. Due to this, it might not be functioning properly. Therefore, in this step, we will be checking and installing new Windows Updates. For that:
Solution 5: Changing AntiSpyware Value in Registry
It is possible that a certain malware or virus installed a script in the registry which prevents the Windows Defender from functioning properly. Therefore, in this step, we will be disabling that value. For that:
Solution 6: Performing a Clean Boot
In rare cases, certain third-party applications or services might be preventing Windows Defender from turning on. Therefore, in this step, we will be initiating a clean boot which will prevent any of these applications from starting. For that:
