The implementation of Health Information Systems (HIS) has been heralded as bringing numerous benefits to the healthcare sector. When implementing a HIS, the attitudes of the various users (nurses, doc-tors, admin people) towards the HIS can be influenced by a number of different factors. User support has proved to be one of the most important ones. Most recently, Sundhedsplatformen, one of the largest public HIS in Denmark, is being implemented in 18 hospitals across Zealand. In this context, we conducted 21 interviews at one of the major hospitals, Rigshospitalet, and qualitatively coded them. This allowed us to explore three archetypical groups of user attitudes toward Sundhedsplatformen: ‘Dedicated’, ‘Frustrated’ and ‘Despondent’. Further, we identified manifestations of insufficient user sup-port on different levels. We clustered these elements into three levels of support: ‘Individual’, ‘Techno-logical’ and ‘Organisational’. Reflecting on the manifestations of insufficient user support enables us to achieve a nuanced and holistic understanding of user support as an important adoption factor and further how user attitudes can be addressed when implementing HIS.