Technologies such as Digital Mock Up (DMU) or Virtual Reality (VR) help to expose and fix design errors at an early stage in the product development process. Nevertheless the discovery of these potential problems is still a common obstacle. The approach introduced within this paper improves the existing virtual product validation method by using the company’s existing knowledge of former projects. The DMU-Cockpit integrates the usually spread experience of known errors in one tool by modelling a relation between classified components and sources of error in a matrix. This allows the automatic selection of potential sources of error for a chosen part and derives the most valuable validation tasks of the knowledge base.