Protection for your PC

Windows Defender is built into the new 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.

Get Microsoft Security Essentials for a PC running Windows 7 or Windows Vista.

What's included

	Microsoft Security Essentials	Windows Defender
	Windows 7, Windows Vista	Windows 8, Windows RT, Windows 8.1, Windows RT 8.1
Real-time protection against spyware, viruses, rootkits, and other malicious software
Online system scanning and cleaning
Dynamic signature service
Offline system scanning and cleaning
Enhanced protection against rootkits and bootkits

Windows Defender for Windows 8, Windows RT, Windows 8.1, and Windows RT 8.1 provides built-in protection against malware. You can't use Microsoft Security Essentials with Windows 8.1, 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 Windows 8 and Windows 8.1, Windows Defender provides full malware protection for your PC. Malware consists of viruses, spyware, and other potentially unwanted software.