The rise of the complexity of products and the product development process in addition to shorter development cycles and the customers’ high demands on quality, increase the pressure on producing as accurately and economically as possible. Hence, it is necessary to avoid errors in the early phases of development instead of fixing them at a later stage, which can be costly. This article uses the product configuration of milling robot units to show an innovative solution for the early development phase. This approach uses established technologies from the area of semantic technologies and problem solving methods. It also shows how to improve the reliability of product configuration by making use of the expertise from later phases in the development.