Follow the steps if Microsoft defender turn back automatically

Disable Tamper Protection - Go to Windows Security > Virus & threat protection > Manage settings and toggle the switch off. Pro Users should use Group Policy by accessing gpedit.msc and navigating to Microsoft Defender Antivirus followed by enabling the Defender disable feature. Apply changes to the Registry System by enabling the DisableAntiSpyware DWORD value with a value of 1 at HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows Defender. Insert this command into the Windows Terminal (Admin) interface: Set-MpPreference -DisableRealtimeMonitoring $true.

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