Microsoft Security Essentials is a free* and easy-to-use software that protects your PC from viruses, spyware, and other malware. It works in the background and updates automatically, and supports Windows Vista and Windows 7.

OneDrive (home or personal) Windows Defender and Microsoft Security Essentials are powerful scanning tools that find and remove malware from your PC. Here's how to use Windows Defender in Windows 8.1 or Microsoft Security Essentials in Windows 7 to scan your PC.

Windows Security is a built-in feature that provides real-time antivirus and malware protection for your Windows 10 or 11 device. Learn how to run scans, customize settings, schedule tasks, and access other security tools and tips.

You can't turn on real-time protection in Microsoft Security Essentials (MSE). Cause. This issue may occur if other security software, such as antivirus, antispyware, or antimalware programs, are fully or partially installed on the computer. Resolution. Make sure that all traces of the security programs that are installed on the computer are ...

More Information. To resolve this issue, upgrade to the latest version of Microsoft Security Essentials. Using the latest version of Microsoft Security Essentials helps make sure that you have continuous protection against viruses, spyware, and other malicious software.

Support for Windows 7 ended on January 14, 2020. We recommend you move to a Windows 11 PC to continue to receive security updates from Microsoft. Learn more. Microsoft Security Essentials works automatically with Microsoft Update to ensure that your virus and spyware definitions are kept up to date.

Learn how to use Microsoft Defender, Windows Update, and OneDrive Personal Vault to stay secure with Windows and online. Find tips, support, and resources for identity theft, scams, and attacks.