Adaptive e-Learning is a process where learning contents are delivered to learners adaptively, namely, the appropriate contents are delivered to the learners in an appropriate way at an appropriate time based on the learners' needs, knowledge, preferences and other characteristics. Social e-Learning is a process where connections are made among like-minded learners, so they can achieve learning goals via communication and interaction with each other by sharing knowledge, skills, abilities and materials. This paper reports an extended case study that investigated the influence of social interactions in an adaptive e-Learning environment, by analyzing the usage of social interaction features of a Social Personalized Adaptive E-Learning Environment (SPAEE), named Topolor, which strives to combine the advantages from both social e-Learning and adaptive e-Learning. We present the results of a quantitative case study that evaluates the perceived usefulness and ease of use. The results indicated high satisfaction from the students who were using Topolor for their study and helped us with the evaluation processes. Based on the results, we discuss the follow-up work plan for the further improvements for Topolor
