 She also studied at the Musikhochschule in Frankfurt, Germany with Helmut Walcha.She has said her work with him was difficult as he "did not believe that women belonged on the organ bench".Harbach was Professor of Music at Washington State University from 1991 to 1997, Visiting Professor of Music at University of Wisconsin–Oshkosh from 1997 to 2000, and Visiting Professor of Fine Arts at the University of Wisconsin–Stevens Point from 2000 to 2003.