Problem : StyleCop warning due to file header missing or mismatch for any “.cs” file.
Warning Message : “The file has no header,the header xml is invalid or the header is not located at the top of the file.”
Error No : SA1633
What I used to do?
I used to follow a dumb approach to save my bit of time. I save the template text in toolbox. And for each file, drag and drop the content from tool box and change the file name.

Two Different approaches to automatically add document header. Well, we have two different approaches to automate this stuff.
1. Using Templates
2. Using Macro
1. Using Templates :
we can rewrite the Visual Studio code templates to customize the templates as per requirements. below is the default template for visual studio classes.
Read more: Abhijit's World of .NET