In rare cases it can happen that you get a missing DLL error message when starting DELTAGEN. This mostly happens due to not properly installed Microsoft Visual Studio redistributables.
Please update your operating system and make sure all necessary Windows updates are installed.
If the DLL file is still missing you can download the most common Redistributable packages directly from the Microsoft website.
For example a missing api-ms-win-crt-runtime-l1-1-0.dll requires the Visual C++ Redistributable for Visual Studio 2015 which can be downloaded here: https://www.microsoft.com/en-in/download/details.aspx?id=48145