"DEBUG=my-application ./bin/www" this command work on mac os. why not working for windows 8. is there any similar command?
From the related question: Why can't I run my node.js express web application.
You cannot set environment variables in Windows in the same manner that you can on unix based systems (Linux, OS X etc.). This is why you are encountering the error: DEBUG is not recognized as an internal or external command, operable program or batch file.