英文版错误信息:

Session state has created a session id, but cannot save it because the response was already flushed by the application.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Web.HttpException: Session state has created a session id, but cannot save it because the response was already flushed by the application.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below. 

Stack Trace:

[HttpException (0x80004005): Session state has created a session id, but cannot save it because the response was already flushed by the application.]
   System.Web.SessionState.SessionIDManager.SaveSessionID(HttpContext context, String id, Boolean& redirected, Boolean& cookieAdded) 2220274
   System.Web.SessionState.SessionStateModule.CreateSessionId() 55
   System.Web.SessionState.SessionStateModule.DelayedGetSessionId() 64
   System.Web.SessionState.SessionStateModule.OnReleaseState(Object source, EventArgs eventArgs) 328
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() 92
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) 64
 

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Version Information: Microsoft .NET Framework Version:2.0.50727.832; ASP.NET Version:2.0.50727.832

中文版本错误信息:

“/”应用程序中的服务器错误。
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会话状态已创建一个会话 ID，但由于响应已被应用程序刷新而无法保存它。
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.Web.HttpException: 会话状态已创建一个会话 ID，但由于响应已被应用程序刷新而无法保存它。

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:

[HttpException (0x80004005): 会话状态已创建一个会话 ID，但由于响应已被应用程序刷新而无法保存它。]
   System.Web.SessionState.SessionIDManager.SaveSessionID(HttpContext context, String id, Boolean& redirected, Boolean& cookieAdded) 2220274
   System.Web.SessionState.SessionStateModule.CreateSessionId() 55
   System.Web.SessionState.SessionStateModule.DelayedGetSessionId() 64
   System.Web.SessionState.SessionStateModule.OnReleaseState(Object source, EventArgs eventArgs) 328
   System.Web.SyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() 92
   System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) 64
 

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版本信息: Microsoft .NET Framework 版本:2.0.50727.312; ASP.NET 版本:2.0.50727.833

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出现这个问题的状态:在添加Session_Start()或者Session_Start()的时候,程序第一次运行的页面带这个错误信息,但是页面内容正常!!!是呼客户断收到了两次信息!!!具体原因不详...

解决方法:

因为我用Response.Flush()发送页面缓存只有用了

Response.End();所以我删除了Flush()的操作,问题解决

我认为End();和Flush()都是发送缓存,但是End()发送换就结束页面,而Flush()发送完还没结束页面的操作...

而Session_Start()可能会在页面结束也就是End()运行当中被调用...只是可能 

至少问题解决了!google上找不到这个问题的解决方法,英文站上也基本都是猜测类的!