• Cause 1: Make sure that “Integrated Windows Authentication” is enabled. Probably, you enabled only “Basic authentication” for Directory security of IIS. • Cause 2: If you are using “Integrated Windows authentication”, you need to make sure that your user account has full control on the directory of the IIS. • Cause 3: 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 IE will impact on the behavior of log on. In this case, you need to enable logging on with your current user account in “Internet” area with IE setting. But it is not the default setting of IE, so you’d be better off if you create project with only the machine name.
原因2：如果您打开了windows集成认证选项的话，确保您的用户帐号具有对IIS目录的完全控制权
原因3：如果您的Web项目使用额完整的机器名作为项目名称(machinename.domainname.something)的话，那么这个Web站点就会被认为是一个Internet站点，所以IE的缺省设置就会影响登陆状态，在这种情况下，您需要在IE设置的Internet区域中允许您使用当前用户帐户登陆；这并不是IE的缺省设置，所以您最好使用你的机器名称来作为您项目的名字！
• Cause 1: Make sure that “Integrated Windows Authentication” is enabled. Probably, you enabled only “Basic authentication” for Directory security of IIS. • Cause 2: If you are using “Integrated Windows authentication”, you need to make sure that your user account has full control on the directory of the IIS. • Cause 3: 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 IE will impact on the behavior of log on. In this case, you need to enable logging on with your current user account in “Internet” area with IE setting. But it is not the default setting of IE, so you’d be better off if you create project with only the machine name.