Program does not contain a static 'Main' method suitable for an entry point

Question

Suddenly my whole project stopped compiling at all, showing the following message:

Program \'path_to_obj_project_folder\' does not contain a static \'

Answer 1

As what, I guess pixparker wanted to say, but remained to be not clear enough, for me at least, do ensure that... All "Other Projects" have an "Output Type" of "Class Library" selected while... Only "One Project" being selected as either "Window Application" or "Console Application" output.