problems with a book

Question

hi, i'm learning c# by this book: "Wrox beginning c sharp 3.0 an introdution...." however the code he puts there never works fine for me. for exemple i have this code: "has more than one entry point defined: "windowsFormsApllication3.Main(). compile with /main to specficy the type that contains the entry point" how can i solve this. sorry im at the begining. (how can i put the code here?)