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You cannot mark grouping controls (tabs, sections, panels and repeats) required. A section is one grouping control that does have a Required Property. If a Section has the required property checked, required controls within it show an asterisk (*) in design and Use mode. If the Section has required unchecked, required controls within it DO NOT show the asterisk (*) in design and Use mode. The asterisk (*) appears only when one of the required controls in the section is filled making it mandatory to fill other required controls within the section.
Input controls that are direct children (directly inside) of repeat controls also cannot be marked required, nor do they need to be, since the min# and max# properties take care of this already. You may, however, make controls required when they are inside sections, tabs and panels.
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