This study presents the results of a sequential explanatory mixed-method approach to investigate the Iranian English language non-gainers of a computerized dynamic reading comprehension test (CDRT) by utilizing a learning style survey. Using an interventionist approach, the researchers used the CDRT software to explore English learners' perceptual learning-style preferences of non-gainers in CDRT. The study participants were selected from among 24 advanced English language learners attending a reading course at a language institute in Iran. The results of Learning Potential Score (LPS) formula categorized six of the participants as non-gainers of CDRT. They were asked to fill out a learning style survey individually and participate in an interview to express their attitudes toward using the software. The findings revealed some common tendencies regarding field-independency, impulsivity/reflectivity, and metaphoric/literal style preferences supported in learners' interviews. In this study, learners' style preferences potentially played an important role in reporting learners' performance; therefore, it is suggested to consider students' learning styles in making decisions about their abilities and disabilities in CDRT.