... A load could not be applied to small or defeatured entity. See the Troubleshooting section of the Help System for more information.

At least one load is not able to be applied. This may be due to mesh-based defeaturing of the geometry. You can modify the mesh defeaturing settings to restore the nodes and elements where the loads need to be applied. Another possible reason could be that the Details View property Send to Solver was incorrectly set to No for the node-based Named Selection used for some Direct FE boundary condition scoping. Additionally, in a Thermal environment, the load applied to a whole body might lose its scope if all pertinent faces have other surface loads applied. See the Resolving Thermal Boundary Condition Conflicts section of the Help for a description of precedence.