IIS 7.5 httpmodule authentication Error
初次错误：
Unable to cast object of type 'System.Security.Principal.GenericIdentity' to type 'CustomSecurity.CustomIdentity'.
解决方案：
将网站应用程序池设置为的“经典模式”。
第二次错误：
解决方案：在Windows Feature中安装asp.net.
第三次错误：
解决方案：
Error Summary
HTTP Error 404.2 - Not Found
The page you are requesting cannot be served because of the ISAPI and CGI Restriction list settings on the Web server.
1. Double click the Server Name “xxxx”, then double click “ISAPI and CGI Restrictions”
（若ISAPI and CGI Restrictions没有在Feature面板中显示，则需要在windows feature中先安装它）
2. Click the 
, then click “Allow” from right panel
