I've basically circumvented the databinding and implemented my own poor version.
I have finally tracked down a bug that I've been working on for the entire weekend, however I don't see a way to really solve it - in a clean way, that is.It looks like the "Row Validating" event DOESN'T fire if the grid is on a MODAL form but it DOES fire when the grid is on a NON-MODAL form. You can run in the immediate window by typing and seeing if you get the Row Validating popup from the handler: Module _Sandbox Test Sub Data Grid View Test Non Modal() Dim frm As New Form Dim dtable As New Data Table() dtable. For additional information about the features available in the Data Grid View control, see Data Grid View Control (Windows Forms). For more information, see Data Display Modes in the Windows Forms Data Grid View Control.I now know the correct way to handle this and have since fixed my code, however I'd still like to know how I could have solved the bug another way.I handle the Row Validating event and do one final validation on the row as a whole to ensure everything is cool.To perform any custom validation on the cell or row being edited, you can use the Cell Validating and Row Validation events, respectively.If you want to validate the data cell by cell, the former event is useful where you want to validate the data for the entire row at once then the later event is handy.Hovering the mouse pointer on the icon displays the Error Text that you set earlier.The Data Grid View control of Windows Forms is a versatile control that can help you create professional-looking data entry forms.