"Object reference" error occurs when control is invalid


An error sometimes occurs when a control becomes invalid and tooltip is placed onto the textbox. Seems like it only happens when the mouse cursor is in the textbox when the control is set to invalid. Error is: "Object reference not set to an instance of an object. as System.Windows.Controls.ToolTipService.OnOwnerMouseLeave(Object sender, MouseEventArgs e)".


benoybose wrote Jul 22, 2009 at 5:36 PM

Can anybody can help on this?

wrote Feb 13, 2013 at 7:57 PM