I have created the material properties and assigned to the correct section, but abaqus still have this problem. anyone could help me out? thank you in advanced
Look at the set for which the property definition is supposed to be missing and look into the inp file whether you really have a solid section for this set; often, a simple typo can be the cause
You should be mindful, the section which you define in Property Module--->Create Section, must be same that you define in Mesh Module--->Assign Element Type.For example, if you create a solid section in property module, so you have to assign solid element to your geometry in mesh module.