Kindly help me out of session time_out.How true is the statement below.Very eagerly waiting to hear for a quick help,please.

As per the details, there are two web servers in load balancing. Suppose, first time a request goes to Server1 for login validation, login is validated and sessions are created. Now when user clicks on topic for assessment, request goes to Server 2 on this occasion but it will not find any sessions (as session is created on Server 1) and hence it will throw an exception for session time out.

And Here is the log file details getting generated:
Stack Trace :
   at System.Web.UI.Page.HandleError(Exception e)
   at System.Web.UI.Page.ProcessRequestMain()
   at System.Web.UI.Page.ProcessRequest()
   at System.Web.UI.Page.ProcessRequest(HttpContext context)
   at System.Web.CallHandlerExecutionStep.System.Web.Htt pApplication+IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionS tep step, Boolean& completedSynchronously)

Error Description :
System.Web.HttpUnhandledException: Exception of type System.Web.HttpUnhandledException was thrown. ---> System.Data.SqlClient.SqlException: Prepared statement '(@TopicID bigint,@UserID nvarchar(4000))SET DATEFORMAT 'dmy';Upd' expects parameter @TopicID, which was not supplied.
   at System.Data.SqlClient.SqlCommand.ExecuteReader(Com mandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream)
   at System.Data.SqlClient.SqlCommand.ExecuteNonQuery()
   at PSG.clsDatabaseLayer.SimpleQueryN(eQueryObjectType e, String strQuery, Object[] ParamValueList)
   at PSG.completecourse.Page_Load(Object sender, EventArgs e)
   at System.Web.UI.Control.OnLoad(EventArgs e)
   at System.Web.UI.Control.LoadRecursive()
   at System.Web.UI.Page.ProcessRequestMain()
   --- End of inner exception stack trace ---
   at System.Web.UI.Page.HandleError(Exception e)
   at System.Web.UI.Page.ProcessRequestMain()
   at System.Web.UI.Page.ProcessRequest()
   at System.Web.UI.Page.ProcessRequest(HttpContext context)
   at System.Web.CallHandlerExecutionStep.System.Web.Htt pApplication+IExecutionStep.Execute()
   at System.Web.HttpApplication.ExecuteStep(IExecutionS tep step, Boolean& completedSynchronously)

Kindly guide me through this.
Thanks

What is the internet server software? Is it IIS?