Additional Microsoft Defender tools and services that provide security across various platforms and environments
Microsoft Security Essentials is the Microsoft antivirus product that runs on Windows 7 SP1.
On a default installation of Windows 7 SP1 there is no built-in antivirus, and Microsoft recommends installing a compatible and supported antivirus application such as Microsoft Security Essentials or a third‑party antivirus product. Note that Windows Defender Antivirus (the built‑in AV) is only available on Windows 8.1 and later, not on Windows 7.
For additional options, reputable third‑party consumer antivirus products that are compatible with Windows are listed in Microsoft’s antivirus provider guidance.
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