I have CF 8 with built in webserver (Window 2003 sever),
I want to get window username ....
I'm not sure exactly what you mean. Do you mean the Windows username of a website visitor?
If so, use IIS instead of the built-in web server, and configure it to require Windows authentication. Then, in your CF code, you can look for CGI.AUTH_USER.
Dave Watts, CTO, Fig Leaf Software