COVID-19 has significantly changed the teaching-learning process and it may indeed be a permanent change. Schools, colleges and universities have had to switch to remote/e-learning in an attempt to continue their operations during the pandemic. Institutions have struggled to identify the key success factors necessary for effective e-learning. While there have been some studies that have identified a few key factors, there has not been a comprehensive review of the key success factors for effective e-learning. This paper fills that gap by presenting a detailed examination of the critical success factors required for effective e-learning. The results show that success in e-learning is a complex combination of key factors such as institutional/administrative support, systems configuration and technical design, the level of computer skills among learners, learners' interpersonal behavior, e-learning readiness, learner motivation, computer anxiety, self-efficacy, instructors' characteristics, environmental factors and the demand it imposes on learners of varying age and cognitive maturity.