Technology mediated learning (TML) is gaining interest from both academic researchers and communication professionals as training with Internet technology and Web-based distance learning become increasingly popular. This paper investigates social norms, individual-level cultural orientation (collectivism), and affective commitment (internalization and identification) and studies their influences on the system users' (or learners') attitude toward sharing knowledge by email in the TML environment. An empirical test of the proposed model was conducted in the pilot test (n=155) and the main test (n=411). Theoretical and practical implications of these findings for TML, knowledge management, and e-collaboration are discussed in the paper.