Server Error in '/' Application.

Item has already been added. Key in dictionary: 'NumberOfUsersOnline'  Key being added: 'NumberOfUsersOnline'

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.ArgumentException: Item has already been added. Key in dictionary: 'NumberOfUsersOnline'  Key being added: 'NumberOfUsersOnline'

Source Error:


Line 32:             }
Line 33: 
Line 34:             int cntOnLine = SessionManager.NumberOfUsersOnline;
Line 35:             this.NowOnSite.Text = "Из них на сайте: " + cntOnLine.ToString();
Line 36:             if (cntOnLine == 0) 

Source File: C:\inetpub\vhosts\u0545844.plsk.regruhosting.ru\prozarium.ru\Controls\LoginToSite.ascx.cs    Line: 34

Stack Trace:


[ArgumentException: Item has already been added. Key in dictionary: 'NumberOfUsersOnline'  Key being added: 'NumberOfUsersOnline']
   System.Collections.Hashtable.Insert(Object key, Object nvalue, Boolean add) +13134420
   System.Collections.Hashtable.Add(Object key, Object value) +16
   System.Collections.Specialized.NameObjectCollectionBase.BaseAdd(String name, Object value) +88
   System.Collections.Specialized.NameObjectCollectionBase.BaseSet(String name, Object value) +45
   System.Web.SessionState.SessionStateItemCollection.set_Item(String name, Object value) +31
   System.Web.SessionState.HttpSessionStateContainer.set_Item(String name, Object value) +16
   System.Web.SessionState.HttpSessionState.Add(String name, Object value) +16
   YourPoint.SessionManager.get_NumberOfUsersOnline() in E:\Projects\CMS\App_Code\SessionManager.cs:801
   YourPoint.Controls_LoginToSite.Page_Load(Object sender, EventArgs e) in C:\inetpub\vhosts\u0545844.plsk.regruhosting.ru\prozarium.ru\Controls\LoginToSite.ascx.cs:34
   System.Web.Util.CalliEventHandlerDelegateProxy.Callback(Object sender, EventArgs e) +52
   System.Web.UI.Control.OnLoad(EventArgs e) +97
   System.Web.UI.Control.LoadRecursive() +61
   System.Web.UI.Control.LoadRecursive() +134
   System.Web.UI.Control.LoadRecursive() +134
   System.Web.UI.Control.LoadRecursive() +134
   System.Web.UI.Control.LoadRecursive() +134
   System.Web.UI.Control.LoadRecursive() +134
   System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +693


Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.8.4690.0