Debugging ASP.NET Applications with VS 2003
after hours of troubleshooting, I found this
If you created the Web project with a full machine name (like machinename.domainname.something), the Web site is recognized as Internet site. So, the default setting of Internet Explorer will impact on the behavior of logging on. In this case, you need to enable logging on with your current user account in “Internet” area with the IE setting.