Although I can say with certainty that it doesn't protect against everything (no anti-virus does), I have been impressed with Windows Defender. The independent lab tests have been ranking it at the top, alongside top performers Kaspersky and Avast!, my go-to AVs for older Windows systems. Windows 10 certainly gets infected far less often than XP, 7, or 8.
Although I can say with certainty that it doesn't protect against everything (no anti-virus does), I have been impressed with Windows Defender. The independent lab tests have been ranking it at the top, alongside top performers Kaspersky and Avast!, my go-to AVs for older Windows systems. Windows 10 certainly gets infected far less often than XP, 7, or 8.
Yeah, as a product I think AV is a wasted purchase if your running Windows 10. Defender is as good if not better than the rest.