Trigger cellvalidating event
Select your Text Box control on your Form and go to Properties window.
To duplicate run the project, with the mouse place focus on the grid and type something in a cell and then with the mouse place focus on the text box on the form and you will notice that the messagebox invalid data appears twice.This message box is in the current cell validating event.Thanks, Steve frm SF_8948This appears to be caused by the dockingmanager. This avoids the problem, but does not validate (even once) when you click off teh grid.If you remove the dockingmanager, the problem goes away. If you want to validate in this case, you can handle the grid.