This problem occurs in the Response.Redirect and Server.Transfer methods because both methods call Response.End internally which ends the page execution and shifts the execution to the Application_EndRequest event in the application's event pipeline. The line of code that follows Response.End is not executed.
To work around this problem, use one of the following methods:
For Response.End, call the HttpContext.Current.ApplicationInstance.CompleteRequest method instead of Response.End to bypass the code execution to the Application_EndRequest event.
For Response.Redirect, use an overload, Response.Redirect(String url, bool endResponse) that passes false for the endResponse parameter to suppress the internal call to Response.End. For example:
Response.Redirect ("nextpage.aspx", false);
If you use this workaround, the code that follows Response.Redirect is executed.
For Server.Transfer, use the Server.Execute method instead.