Information technology is part of a growing number of applications in work and everyday life. It seems inevitable that the average person soon will have to interact with information technology in many ways, even when there is no desire to do so. Examples include finding a book in a library, personal financial transactions, the health sector, traffic and transportation, process control, etc. People who in this way are forced to interact with information technology shall be called accidental users. The accidental user poses a particular challenge to the design of technological artefacts because the disciplines of dealing with human-machine interaction are predicated on the assumption that users are motivated and have a minimum level of knowledge and skills. In particular, models of human error and human reliability implicitly assume that users are benign and only fail as anticipated by designers. In this paper we investigate the extent to which current models of human erroneous actions and cognitive reliability can be used to account for interactions between accidental users and technology.