Here's the stack trace when the exception is thrown:
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Visual Studio Just-In-Time Debugger
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An unhandled exception ('Unhandled Error in Silverlight Application
Code: 4004
Category: ManagedRuntimeError
Message: System.InvalidOperationException: Cannot call BeginEdit() on Deleted or Detached entities
at IdeaBlade.EntityModel.EntityWrapper.System.ComponentModel.IEditableObject.BeginEdit()
at Infragistics.Silverlight.Controls.XamWebGrid.EnterEditModeInternal(Row row, Cell cell)
at Infragistics.Silverlight.Controls.XamWebGrid.EnterEditMode(CellBase cell)
at Infragistics.Silverlight.Controls.XamWebGrid.SetActiveCell(CellBase cell, CellAlignment alignment, InvokeAction action, Boolean allowSelection, Boolean
setFocus, Boolean scrollIntoView)
at Infragistics.Silverlight.Controls.XamWebGrid.SetActiveCell(CellBase cell, CellAlignment alignment, InvokeAction action, Boolean allowSelection, Boolean
scrollIntoView)
at Infragistics.Silverlight.Controls.XamWebGrid.SetActiveCell(CellBase cell, CellAlignment alignment, InvokeAction action, Boolean allowSelection)
at Infragistics.Silverlight.Controls.Cell.OnCellMouseDown(MouseEventArgs e)
at Infragistics.Silverlight.Controls.XamWebGrid.c(Object A_0, MouseButtonEventArgs A_1)
at System.Windows.CoreInvokeHandler.InvokeEventHandler(Int32 typeIndex, Delegate handlerDelegate, Object sender, Object args)
at MS.Internal.JoltHelper.FireEvent(IntPtr unmanagedObj, IntPtr unmanagedObjArgs, Int32 argsTypeIndex, String eventName)
') occurred in iexplore.exe [4980]. Just-In-Time debugging this exception failed with the following error: No installed debugger has Just-In-Time debugging
enabled. In Visual Studio, Just-In-Time debugging can be enabled from Tools/Options/Debugging/Just-In-Time.
Check the documentation index for 'Just-in-time debugging, errors' for more information.
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OK
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