I need to activate the current cell in the _AfterCellUpdate event after the error message is shown to tell the user that the value of the cell is wrong.  But the next cell is activated when the tab is pressed.

The code below shows that I am doing everything to keep the focus on the same cell, but the focus is moved to the next cell!

        void ultraGridUM_AfterCellUpdate(object sender, Infragistics.Win.UltraWinGrid.CellEventArgs e)
        {
            if (e.Cell.Column.Key == "Code" && e.Cell.Value!=null)
            {
                foreach (Infragistics.Win.UltraWinGrid.UltraGridRow row in this.ultraGridUM.Rows)
                {
                    if (row != e.Cell.Row)
                    {
                        if (row.Cells["Code"].Value != DBNull.Value)
                        {
                            if (String.Compare(row.Cells["Code"].Value.ToString(), e.Cell.Value.ToString().Trim()) == 0)
                            {
                                MessageBox.Show("Wrong value.");
                                e.Cell.Value = e.Cell.OriginalValue;
                                this.ultraGridUM.ActiveRow = e.Cell.Row;
                                this.ultraGridUM.ActiveCell = e.Cell;
                                this.ultraGridUM.PerformAction(Infragistics.Win.UltraWinGrid.UltraGridAction.EnterEditMode,false,false);
           
                                return;
                            }
                        }
                    }
                }
            }
        }