During the elastic analysis, you get the warning:

[NL]: WARNING: Probleem in *naam van de combinatie* : grote vervormingen in volgende kno(o)p(en): 1-33

[FR]: WARNING: Problème dans *nom du combinaison*: grandes déformations dans le(s) nœud(s) suivant(s): 1-33

[ES]: WARNING: Problema en *nombre de la combinación*: deformaciones extremadamente altas en los siguientes nodos: 1-33

Notes:

• The name of the combination (here Dead loads) can be different in your project. One or more combinations can give this error.
• The node numbers mentioned in the warning refer to the nodes in the mesh, not the points.

Solution

• Click ‘Finish’ to close the window
• Go to the relevant combination.
• Check all deformations . Don’t forget that angular displacement, is also a displacement.
• The size fo the large deformations represents the structure being a mechanism is a certain direction.
• Adjust the structure so the relevant load can be beared.
  Note: if a structure contains hinges, it is possible to many hinges are applied. To test this, remove the hinges and calculate again. It is recommended to add hinges in steps and calculating the structure between each add. This way mistakes can be easily found.

Example:

The simple supports are not able to take the torsional moment evoked by the point load. Diamonds will give the large displacement warning.