Understand complex datatype (structures) restrictions and limitations.
Instead of having multiple parameters referencing the same structure, copy and paste the structure object so that each reference is to a single structure object.
"Structure type:'' < structure_name > '' can't be deleted, because it is still referenced by personalization key : '' < PK_name > ''".A Cut or Delete of a structure in the object diagram generates a similar error message if the structure is still referenced by a parameter or other structure .