Several policies for e-government, both on national and supranational levels, express visions and claims for more advanced exploitation of digital opportunities. The paper contributes through a problematization of the idea of utilizing digital opportunities and a conceptualization of this into the polarity of overexploitation vs. underexploitation of digital opportunities. It is based on a qualitative and diagnostic case study on the digitalization of medical certificates and theoretically informed by affordance theory and activity theory. Digital arrangements in the case study are investigated and different types of digital affordances and constraints are revealed. There are examples of surplus of affordances (i.e. overexploitation), lack of affordances and affordances with embedded constraints (i.e. underexploitation), and useful affordances (i.e. adequate exploitation). The application of the affordance and constraint concepts is, in the paper, done through a two-step staging: 1) General characteristics of digital technology give affordances for design. 2) The resulting digital artifacts will have different properties and these properties give affordances but also constraints for use. The resulting conceptualizations are discussed in relation to normative, regulative and other institutional aspects concerning digitalization in the public sector. This is conceptualized in a graphical model describing policy and other pre-conditions, designed digital artifacts, and workpractice effects.