a bug in tetra meshing

This is not a bug.Before converting mesh into tetras, please make sure that the 2d surface mesh should be enclosed.If possible share hm file to check same at our end.

this is my file. if you mesh it, I will be appreciate to get the hint from you. thanks alot

Unable to find an attachment - read this blog

another thing I should to add is, if you can use only one of the 3 layers and cylinder to mesh. it tell me another error that I could not find the solution.

Hello Rahul. I did not get any answer from you.. could you please answer me?

I see all three layers are not connected.I also see one cylinder around three layer.What type of analysis you are going to perform ?

Do you want tetramesh considering Cylinder and three layer mesh? 

yes. it is scaffold of the bone.  and I want to use the volume mesh for fluid analyzes. when I want to mesh only one of layers and the cylinder it again tell me an error that I do not know how to fix it. could you only volume mesh one of layer with the cylinder and tell me my error?

one of my problem is I could not change the quality of the layers' mesh because I got this mesh from point clouds and I did not have the surface from them. I tried to sketch the surface from FE for meshing it myself, but the surfaces does not have much quality because of the complexity of the geometry and the meshes. I do not have any more idea. and I will be appreciate if you could help me.

also the three layers are not connected because they are imported separately.  also FYI I got the surfaces from an implicit equation..

your shared hm file is too big to handle in my laptop.I see mesh is also very complex.This can also be done in Altair Simlab Preprocessor.Refer below youtube video for same.Also please let me know which option you use to generate tetramesh in Hypermesh?