why doesn't .net framework install
Troubleshooting Blocked .NET Framework Installations and Uninstallations. When you run the web or offline installer for the .NET Framework 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, or 4.6.2, you might encounter an issue that prevents or blocks the installation of the .NET Framework. The following table lists possible blocking issues and provides links to troubleshooting information.