The official website doesn't provide any information related to the troubleshooting of the software. I recommend you remove everything that you can about the NET FRAMEWORK package and then reinstall the latest version (old version is recommended as well).
Additionally, launch the following tool to fix errors with the Net Framework: https://www.microsoft.com/en-us/download/details.aspx?id=30135
Although you have the latest version of NET Framework installed, some applications require a specific version, therefore, check the system requirements of ESSL Smart Office and then download the version you need.