The Application Compatibility Toolkit (ACT) enables software developers, independent software vendors (ISVs), and IT professionals who work in a corporate environment to determine, before rolling out within the organization, whether their applications are compatible with a new version of the Microsoft® Windows® operating system. ACT also enables such individuals to determine how an update to the new version will impact their applications.

You can use the ACT features to:
  • Verify an application's compatibility with a new version of the Windows operating system, or a Windows Update, including determining your risk assessment.
  • Become involved in the ACT Community, including sharing your risk assessment with other ACT users.
  • Test your Web applications and Web sites for compatibility with new releases and security updates to the Windows® Internet Explorer® Internet browser.

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