Microsoft Security Essentials
Microsoft Security Essentials provides real-time protection for your home or small business PC that guards against viruses, spyware, and other malicious software.
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11.7 MBMicrosoft Security Essentials is a free* download from Microsoft that is simple to install, easy to use, and always kept up-to-date so you can be assured your PC is protected by the latest technology.
Microsoft Security Essentials runs quietly and efficiently in the background so you’re free to use your Windows-based PC the way you want—without interruptions or long computer wait times.
Before installing Microsoft Security Essentials, we recommend that you uninstall other antivirus software already running on your PC. Running more than one antivirus program at the same time can potentially cause conflicts that affect PC performance.
Supported Operating Systems
Windows 7, Windows Vista
- Minimum system requirements for Microsoft Security Essentials
- For Windows Vista and Windows 7, a PC with a CPU clock speed of 1.0 GHz or higher, and 1 GB RAM or higher.
- VGA display of 800 × 600 or higher.
- 200 MB of available hard disk space.
- An Internet connection is required for installation and to download the latest virus and spyware definitions for Microsoft Security Essentials.
- Internet Browser
Operating System: Windows Vista (Service Pack 1, or Service Pack 2)*; Windows 7*
- Click the Download button on this page to start the download, or choose a different language from the drop-down list and click Go.