Some viruses or spywares create entries in your Windows registry so that they can automatically restart with the reboot of Windows. And if you try to delete them, you may get an “Access is denied” messsage.
To delete such stubborn/locked registry key entries, there is a freeware application called RegASSASSIN by Malwarebytes. RegASSASSIN can remove access denied registry entries by resetting the key’s permissions and then deleting it. This software should be used with care after backing up the registry.

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