You can use FormCalc to check, if the entered text is a valid date. Add
this script in the exit event of your text field. Ensure the selected
programming language is FormCalc not JavaScript.if
(Date2Num(Parse("DD/MM/YYYY", $), "YYYY-MM-DD") eq 0) then if
($host.messageBox("Enter a Date in the format DD/MM/YYYY.", "Wrong
Date", 0, 0) eq 1) then $host.setFocus($.somExpression) endifendif