Protection for your PC


Windows Defender is built into the latest versions of Windows and helps guard your PC against viruses and other malware.

For a PC running an older version of Windows, you can download Microsoft Security Essentials.

Download Microsoft Security Essentials

What's included

Microsoft Security Essentials Windows Defender

Microsoft Security Essentials

Windows 7, Windows Vista

Windows Defender

Windows 8, Windows RT, Windows 8.1, Windows RT 8.1, Windows 10

Real-time protection against spyware, viruses, rootkits, and other malicious software

Microsoft Security Essentials
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Windows Defender
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Online system scanning and cleaning

Microsoft Security Essentials
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Windows Defender
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Dynamic signature service

Microsoft Security Essentials
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Windows Defender
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Offline system scanning and cleaning

Microsoft Security Essentials
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Windows Defender
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Enhanced protection against rootkits and bootkits

Microsoft Security Essentials

Windows Defender
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Windows Defender for Windows 8, Windows RT, Windows 8.1, Windows RT 8.1, and Windows 10 provides built-in protection against malware. You can't use Microsoft Security Essentials, but you don't need to—Windows Defender is already included and ready to go. But if you’re looking to protect a PC with an older version of Windows, you can use Microsoft Security Essentials to help guard against viruses, spyware, and other malicious software. It provides free* real-time protection for your home or small business PCs.

Note: Windows Defender is also available in earlier versions of Windows. However, in earlier versions Windows Defender only provides protection against spyware. In the last versions of Windows, Windows Defender provides full malware protection for your PC. Malware consists of viruses, spyware, and other potentially unwanted software.

The Windows you know, only better

Get to know the latest features in Windows 10.

Learn more

Windows device running Windows 10

See more


Learn ways to help prevent malicious software from being run on your PC.

Get the latest to keep your PC up-to-date and running smoothly.

A wide range of apps and handy add‑ons to help you get the most out of your PC.

Find info about virus removal, security settings, Windows Firewall, and other ways to protect your PC.