Problem

When a .MXD file is opened in ArcMap, which has a Bentley Hydraulics and Hydrology model attached, a "Microsoft .NET Framework" error appears with the following details.

System.NullReferenceException: Object reference not set to an instance of an object.
   at Haestad.Drawing.Control.Application.GraphicalParentFormUIModelBase.HandleActiveSelectionEventChannel_ActiveSelectionChanged(Object sender, ActiveSelectionChangedEventArgs e)
   at Haestad.Framework.Support.ActiveSelectionChangedEventHandler.Invoke(Object sender, ActiveSelectionChangedEventArgs e)
   at Haestad.Framework.Support.ActiveSelectionEventChannel.OnActiveSelectionChanged(Object selection, Boolean ensureVisible)
   at Haestad.Framework.Windows.Forms.Components.HaestadDockingUserControl.NotifyActiveSelectionEdited()
   at Haestad.Framework.Windows.Forms.Components.ProjectExplorerListViewControl.listViewControlProjectExplorer_SelectionEdited(Object aobject, SelectionEditedEventArgs e)
   at Haestad.Framework.Windows.Forms.Components.ListViewControl.OnSelectionEdited(Object sender)
   at Haestad.Framework.Windows.Forms.Components.ListViewControl.ListView_DoubleClickEvent(Object sender, EventArgs e)
   at System.Windows.Forms.Control.OnDoubleClick(EventArgs e)
   at System.Windows.Forms.ListView.WndProc(Message& m)
   at Haestad.Framework.Windows.Forms.Components.ListViewEx.WndProc(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Solution

Make sure you are using compatible versions of ArcMap and the Bentley Hydraulics and Hydrology Product.

Click here for a list of compatible versions.

See Also

AutoCAD Integration Troubleshooting

Platform Compatibility

Downloading OpenFlows | Hydraulics and Hydrology Software