This research investigates a conventional professional work practice and hesitant attitudes and feelings related to an introduction of a social media tool for communication and collaboration. The study was conducted at a wellestablished, international product development company in the electronic industry. Semi-structured in-depth interviews were carried out with engineers from the company's R&D site. Based on the data analysis, the key findings focus upon a perception of Social Media Discomfort (SMD). Factors that constitute SMD can be divided into factors relating to arenas of social interaction (socialness) and into factors mirroring a goal-orientation in attending to work duties (usefulness). The study extends our understanding of why people might reject new social media tools. The results of this study indicate that it happens if the tools are perceived as disconnected to established structures, tools, norms and ideals shared in the workplace. The SMD occurs especially in connection with the adoption of the tool. Understanding the dual nature of uncertainty, i.e. socialness and usefulness, in relation to new social media tools is of relevance for both practitioners and scholars working with issues of the increasingly complex information environment at work.