WCF服务操作 - GET因404失败

I have a WCF service which works on my dev machine running IIS 7, but my coworker is running IIS 5.1 (XP). He can view the service in a web browser when he navigates to the service page, but if he tries to call an operation or navigate to it in his web browser he gets a 404 error. I have a WCF service which works on my dev mach