classic ASP.NET Custom error page not displaying error message

Hi tsakumar81,

Where are you Applied session in programing Please explain in details ?

I have the below code in Global.asax.cs, now I get the expected ouput if I comment only the server,transfer line. Earlier I also commented the line which sets session value.

protected void Application_Error(Object sender, EventArgs e) { if (HttpContext.Current.Session == null) return;

Exception exception = HttpContext.Current.Server.GetLastError().GetBaseException(); if (exception != null) { HttpContext.Current.Session["Error"] = exception; HttpContext.Current.Server.Transfer("~/Error.aspx"); } }

Try

    void Application_Error(object sender, EventArgs e)
    {
        // Get the last unhandled exception that occurred
        Exception exc = Server.GetLastError();

        // Log the exception (optional but recommended for debugging)
        // Example: LogToDatabase(exc);
        // Example: LogToFile(exc.ToString());

        // Clear the error to prevent the default ASP.NET error page from showing
        Server.ClearError();

        // Redirect to a custom error page
        // You can pass error details as query string parameters if needed
        Response.Redirect("~/ErrorPage.aspx?message=" + Server.UrlEncode(exc.Message));
    }

System did not redirect to error page all times, stack trace was displayed in browser and it was raised as a vulnerability issue.

I have removed from Global.asax.cs and added in Web.config as 

<customErrors mode="On" defaultRedirect="~/customerrors/ErrorPage.aspx" />