Modern Malwarebytes installers are signed with SHA-2 certificates. You must have the [KB4474419 update](https://www.catalog.update.microsoft.com/Search.aspx?q=KB4474419 Windows 7) installed from the [Microsoft Update Catalog](https://www.catalog.update.microsoft.com/Search.aspx?q=KB4474419 Windows 7) to allow the installer to run.

Depending on your specific needs, there are three primary official sources:

Required for downloading the installer, initial activation, and receiving threat intelligence updates. Where to Download

Downloading and installing Malwarebytes on Windows 7 remains a viable way to secure an aging operating system, provided you use the compatible or the dedicated legacy v3.x installer . While Newer versions (v5.x+) prioritize Windows 10 and 11, Malwarebytes continues to offer core protection for Windows 7 SP1 for as long as technically possible. Core Compatibility and Requirements

To successfully run Malwarebytes on Windows 7, your system must meet specific software patch requirements due to security certificate changes made by Microsoft:

Free Antivirus 2026 | 100% Free & Easy Install - Malwarebytes

This is the minimum required version.