Hi again :-)
I guess you use my suggestion to enter data into MSHFlexGrid, which is read-only, using TextBox.
In VB there is also Validate event (in your case on TextBox), which you can use to validate user input before writing it to RecordSet behind the MSHFlexGrid.
Remember only that there are possibility this event to not fire. Every control in VB has property CausesValidation with default value True. You should not change this value. It's purpose is for control of raising Validate event. WHEN YOU MOVE FOCUS FROM ONE CONTROL TO ANOTHER, VALIDATE EVENT OF THE FIRST CONTROL IS RAISED ONLY IF CausesValidation PROPERTY OF THE SECOND CONTROL IS SET TO True!