After installing .NET 4.5, our existing code that currently runs on .NET 4.0 is throwing exceptions when assigning data source to DataGridView (note that it was working fine before .NET 4.5, and continues to work when 4.5 is uninstalled... but for several reasons we have to have .NET 4.5 on clients computers):

dgrManagers.DataSource = mManagers;

//where mManagers is System.Collections.ObjectModel.ObservableCollection<IManager>; the collection has 0 items.

//and dgrManagers is an instance of class that extends from Infragistics UltraGrid (Infragistics.Win.UltraWinGrid.v5.2.dll, v5.2.20052.1053).

//Extending is for style purposes, no grid content is referenced.

Previous to this, the grid was initialized (once) with:

foreach (UltraGridColumn c in dgrManagers.DisplayLayout.Bands[0].Columns)
            {
                switch (c.Key)
                {
                    case "FullName":
                        c.Header.Caption = "Full name";
                        c.Header.VisiblePosition = 0;
                        c.Width = dgrManagers.Width - 30;
                        break;
                    default:
                        c.Hidden = true;
                        break;
                }
            }

            dgrManagers.HasLayout = true;

Errors specifics:

HResult: -2147024809

Assemlby: {Infragistics.Shared.v5.2, Version=5.2.20052.1053, Culture=neutral, PublicKeyToken=7dd5c3163f2cd0cb}

Key already exists Parameter name: Key

   at Infragistics.Shared.KeyedSubObjectsCollectionBase.ValidateKeyDoesNotExist(String key, IKeyedSubObject ignoreObject)
   at Infragistics.Shared.KeyedSubObjectsCollectionBase.ValidateKey(String key, IKeyedSubObject ignoreObject)
   at Infragistics.Shared.KeyedSubObjectsCollectionBase.ValidateKey(String key)
   at Infragistics.Shared.KeyedSubObjectsCollectionBase.InternalAdd(IKeyedSubObject obj)
   at Infragistics.Win.UltraWinGrid.ColumnsCollection.InternalAdd(UltraGridColumn column)
   at Infragistics.Win.UltraWinGrid.UltraGridBand.InitColumns(UltraGridBand[] oldBands)
   at Infragistics.Win.UltraWinGrid.UltraGridBand.InitListManager(BindingManagerBase bindingManager, String dataMember, UltraGridBand[] oldBands)
   at Infragistics.Win.UltraWinGrid.UltraGridLayout.ListManagerUpdated(BindingManagerBase bindingManager)
   at Infragistics.Win.UltraWinGrid.UltraGridLayout.ListManagerUpdated()
   at Infragistics.Win.UltraWinGrid.UltraGridBase.Set_ListManager(Object newDataSource, String newDataMember)
   at Infragistics.Win.UltraWinGrid.UltraGridBase.set_DataSource(Object value)

I understand this is an old version of Infragistics, but we're not ready to switch to new one (even though we have some newer licences) since the project is quite huge and has been working for quite some time, and I'm afraid it would cause even more errors if the new version is not fully backward compatible.

Does anyone have any idea how to circumvent this problem? Any help/hint is appreciated...

Thanks,

Veljko