The Reunion Island University uses a set of digital tools for face training and distance learning. The "Digital Technology Observatory" of the University launched a major survey among users to find out if these tools are suitable. This survey was supplemented by an analysis of the traces left on the different tools. Here we are particularly interested in the CSCW tool. We show that, if according to the survey, the CSCW platform is suitable for all users, trace analysis shows that it is not really used for CSCW but primarily for file sharing. Moreover, according to the different training programs, the tool is used differently. Finally, CSCW appears essentially when there is Ministerial Guideline for doing it.