This study aims to model and test the causal relationships among the antecedent and consequent variables of network externalities and switching costs from the consumer perspective. Survey data obtained from office workers and students regarding computer operating systems were used to test hypotheses through covariance structure analysis and conjoint analysis. The hypothesis testing results showed that the sources of network externalities and switching costs had significant effects on consumers' intentions to continue using existing technology. Regarding consumers' switching costs, firms' preannouncement of technology had a positive (+) effect, while expertise and compatibility between competing technologies had negative (−) effects. Furthermore, technology preannouncement had positive (+) effects on all sources of network externalities, namely the installed user base, complementary technology compatibility, and upgradability. These results represent contributions to the research areas of increasing returns to adoption, first-mover advantage, transaction cost theory, and technology preannouncement. The implications of this study for firms in highly interdependent high-technology markets are as follows. First, leading firms seeking to adopt an open technology policy should consider the trade-off between network effects and competitive effects. Second, it is advisable for late entrants to adopt a strategy of expanding their technology network by targeting consumers with extensive expertise as their primary market. Third, firms' preannouncement of technology can achieve both the effect of generating network externalities for consumers and the effect of preventing switching to competing technologies.