As training is increasingly integrated in the workplace and embedded in work technology, trainees are confronted by a variety of workplace and technological interruptions. This article presents a conceptual framework characterizing different types of interruptions and the extent to which they disrupt learning. A longitudinal design was then used to examine the effects of one form of interruption — technical difficulties — on trainees’ (N = 530) self-regulatory processes, learning, and attrition from Web-based instruction. Test scores were 1.33 points lower (out of 20) in modules where trainees encountered technical difficulties. Technical difficulties also had differential effects on attrition rates over time with attrition from the first module being 10 percentage points higher for trainees who encountered these interruptions. Technical difficulties increased negative thoughts and impaired learning more for trainees who dropped out than those who completed the course. Finally, the negative effects of technical difficulties on self-regulatory processes were less for trainees with high technology self-efficacy, but self-efficacy did not mitigate the negative effects of technical difficulties on learning. The implications of these findings for future research and practice are discussed.