Most of empirical research about users' resistance toward IT has been conducted after IT been implemented in organizations surveyed. Few longitudinal research have been done about the way individual and group resistances emerge and evolve during prior stages of projects. This focus on preimplementation phases is all the more important that IS managers need to anticipate potential conflicts and users’ resistances likely to involve project failure. This article delivers the results a two year longitudinal research conducted at Netia corp. (a worldwide leader in video and audio broadcasting) during preliminary phases of its ERP implementation project. As main findings, while conflicts toward IT implemented are often considered as having negative effects and requiring to be actively managed by the hierarchy, the case study delivers an alternative observation: it describes how an affective oriented conflict has been solved while managers adopted an “avoiding management style”. Our observations differ from several prior studies about conflict management styles and support that an avoiding management style can drive team’s members to cope efficiently with conflict situations during IT pre-implantation phase. In conclusion, the article presents research perspectives associated to these results.