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Default mesh set this flag as default, not explictly explicitly set to Mesh or No mesh.
It has to be considered that the mesh of an entity can be generated by GiD in order to generate the mesh of a higher level entity (for instance, to generate the mesh of a volume, the mesh of its surfaces is generated first). In this cases, the mesh of the lower entity (in the example, the surface one), is deleted automatically after generating the higher level one.
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