Editor+VS and downloaded projects

I am unable to open the cpp files because of missing .sln for the downloaded projects, the same thing happens when I am starting a new project based on the templates and I forget to build it through the first time it is opened in Visual Studio, if I close visual studio and the editor without building, the project is saved but missing .sln which I can’t open in the editor anymore because it claims a certain file isn’t compiled.

Look at this post: https://answers.unrealengine.com/questions/14280/generate-vs-project-files-by-command-line.html