Now I could not try this becuase of the missing data, but I would suggest you try this code.
private bool over55 = false;
private void gridDataBoundGrid1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
{
int row, col;
this.gridDataBoundGrid1.PointToRowCol( new Point( e.X, e.Y), out row, out col);
if ( col == 5 && row == 5 && !over55)
{
if ( myToolTip.Active == true)
{
Debug.WriteLine( "De-activating hover");
myToolTip.Active = false;
}
else
{
Debug.WriteLine( "Activating hover");
myToolTip.SetToolTip( this.gridDataBoundGrid1, "hello from tooltip");
myToolTip.Active = true;
}
over55 = true;
}
if ( col != 5 || row != 5)
over55 = false;
}