Hi Mrinalini,
It seems that you have used a MessageBox in the CellValidating event handler to show the users some message. If so, I am afraid this is not a good practice to use a MessageBox without setting the e.Cancel in the validation event. Usually we use MessageBox to show the error and keep the focus in the validating control by setting e.Cancel to true.
However, we can use the Spy++ to monitor the Windows messages that the Button receives. You will find this is duo a WM_LBUTTONDOWN message.
Hope this helps.
Best regards.
Rong-Chun Zhang
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