This study employed Walsh's (2006) concept of classroom interactional competence to investigate the classroom interaction during synchronous online English language teaching. The data of this study is comprised of 8 40-minute video recordings of an EFL class at a state university's English preparatory program. The data belongs to the same group of learners who were taught by the same EFL instructor. The classes were held via ZOOM, a free video-conferencing program. The analysis focused on scaffolding moves of the teacher- specifically reformulation, extension, and modeling moves- for two reasons. First, the data was abundant in terms of teacher talk samples falling into this category. Second, several scaffolding attempts of the teacher were observed to fail due to technology-related problems. There was evidence in the data that the lack of body language harmed the dialogic nature of teacher-learner interaction and reformulation, and extension moves could not bring about extended learner turns. Regarding the unsuccessful modeling, it was observed that the teacher's failure to use annotation tools hindered the learners' noticing of teacher modeling. As a result, these findings have implications for foreign language teachers' adaptation to online teaching and also for the optimization of video-conferencing tools to be developed for educational use.