Normative systems (norms) have been widely proposed as a technique for coordinating multi-agent systems (MAS). The automated synthesis of norms is a complex problem that remains open. IRON (Intelligent Robust On-line Norm synthesis mechanism) is a novel mechanism for the on-line automated synthesis of norms for MASs. IRON produces conflict-free norms that characterise necessary conditions for coordination, without over-regulation. In the past, IRON successfully regulated a traffic scenario even in the presence of non-compliant agents. In this paper, we apply IRON to synthesise norms for a virtual community scenario, where agents are users that share contents within the community. As a result, IRON synthesises norms that prevent users from uploading undesirable contents (i.e., those that users complain about).