Hi Nuria, There is no way to validate custom text parameters (other than making them required, or being a valid datatype; eg Text, Date, Number, etc). The closest solution (albeit reactive) is to use a calculated parameter and/or Advanced settings in a view to highlight whether the data entered is valid (eg make the column "red" in a list view if the date is greater than today). Regards, Doug Doug Den Hoed - AtAppStore Got Skills? Lend a hand!
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