how to Retrieve copied(.asm) file by using j link programme.

Dear Sudhan

Maybe your Modeldescriptor isnt correct, but it is not shown in the image.

this usually works :

   ModelDescriptor modeldesc = pfcModel.ModelDescriptor_Create(ModelType.MDL_PART, "modelNameAsString",null);

   Model model = session.RetrieveModel(modeldesc);

for ASM change the ModelType to ModelType.MDL_ASSEMBLY