In order to prevent the error message from appearing in SHAPE-THIN 8, and ensure that the calculation will start, it is necessary to assign the material to the corresponding point elements as follows:
- Right-click the entire cross-section: "Reduce Cross-Section into Elements".
- Select the corresponding elements or all point elements with the "Insert" status using the Views navigator, because these can only be used to define the material (in contrast to the point elements with the "Remove" status).
- Assign the corresponding material and click OK to confirm.
- Deactivate the visibility.
- Select all elements and right-click one of the selected elements: "Create Cross-Section from Selected Elements".