You can download Microsoft .NET framework at this link:
What is .net?
Fast Video Cataloger is built on the Microsoft .NET framework to ensure you as a user the best and most secure experience. This is why you need .NET installed on your PC before installing Fast Video Cataloger. Microsoft .NET (pronounced “dot net”) is developed by Microsoft to make developing powerful software smarter. .NET provides tools and libraries that enable developers to create Windows software much faster and easier. .NET benefits end-users by providing applications of higher capability, quality and security. The .NET Framework must be installed on a user’s PC to run .NET applications.
This is how Microsoft describes it: “.NET is the Microsoft Web services strategy to connect information, people, systems, and devices through software. Integrated across the Microsoft platform, .NET technology provides the ability to quickly build, deploy, manage, and use connected, security-enhanced solutions with Web services. .NET-connected solutions enable businesses to integrate their systems more rapidly and in a more agile manner and help them realize the promise of information anytime, anywhere, on any device.” See Microsoft for more information.