When in doubt, install the latest supported .NET Framework for your operating system (currently 4.8.1). It is backward compatible with nearly every application ever written for 4.x.

To understand why "4.3" is a ghost, we must look at Microsoft's release history.

The .NET Framework 4.3 offline installer is a useful tool for installing .NET Framework 4.3 on Windows systems without an active internet connection. By following the steps outlined in this guide, you can successfully download and install .NET Framework 4.3 offline installer and ensure that your applications run smoothly.