我按照论坛上的做到2级目录 可以进后台不过前台浏览出现

Server Error in '/' Application. Runtime Error Description: An application error occurred on the server. The current custom error settings for this application prevent the details of the application error from being viewed remotely (for security reasons). It could, however, be viewed by browsers running on the local server machine.

Details: To enable the details of this specific error message to be viewable on remote machines, please create a <customErrors> tag within a "web.config" configuration file located in the root directory of the current web application. This <customErrors> tag should then have its "mode" attribute set to "Off".

<!-- Web.Config Configuration File --><configuration>    <system.web>        <customErrors mode="Off"/>    </system.web></configuration>

Notes: The current error page you are seeing can be replaced by a custom error page by modifying the "defaultRedirect" attribute of the application's <customErrors> configuration tag to point to a custom error page URL.

<!-- Web.Config Configuration File --><configuration>    <system.web>        <customErrors mode="RemoteOnly" defaultRedirect="mycustompage.htm"/>    </system.web></configuration>

在IIS上预览也出现错误
请问怎么解决呢

环境是.NET 2.0 装了MDAC，也改过Off True这些

换成了.net 1.1 后 又出现了这个

“/”应用程序中的服务器错误。
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指定的转换无效。
说明: 执行当前 Web 请求期间，出现未处理的异常。请检查堆栈跟踪信息，以了解有关该错误以及代码中导致错误的出处的详细信息。

异常详细信息: System.InvalidCastException: 指定的转换无效。

源错误:

执行当前 Web 请求期间生成了未处理的异常。可以使用下面的异常堆栈跟踪信息确定有关异常原因和发生位置的信息。 

堆栈跟踪:


[InvalidCastException: 指定的转换无效。]
  wqios.web.SetUp.SetAppSettings(XmlDocument xmldoc, String[,] AppSettingsArray)
  wqios.web.SetUp.BtSave_Click(Object sender, EventArgs e)
  System.Web.UI.WebControls.Button.OnClick(EventArgs e) +108
  System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) +57
  System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) +18
  System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +33
  System.Web.UI.Page.ProcessRequestMain() +1262




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版本信息: Microsoft .NET Framework 版本:1.1.4322.2407; ASP.NET 版本:1.1.4322.2407