Cheating and academic dishonesty have always been the oldest and largest challenges of educational settings, which with the leverage of electronic technology (E-tech), have gained a hidden form in the new environment. The present study investigated the challenging hidden face of the evaluation system of open and distance education universities. It was a descriptive field study (quantitative and qualitative). Three hundred and twenty students answered the four research questions and 286 faculty members and test designers of Payam Noor University completed a questionnaire with Cronbach Alpha of 0.96 on administration methods (in-person, distance, traditional, electronic, conditions and invigilation) for ensuring secure testing. For better perception of the students’ problems in evaluation and finding ways to prevent plagiarism, a semi-structured interview was conducted with seven experienced final-test designers of open and distance education university of Payam Noor. Due to taking in-person exams and invigilation, the students noted that cheating was difficult in exams, and only 10% of them reported cheating within two semesters. It was also found that 62% of students copy assignments, 30% do assignments with the help of others, 18% copy without citation, and 4% hand in the entire paper as their own work. Moreover, the students believed that 81% of other students cheated in exams, 54% in doing assignments, and 45% in coping without citation. All the instructors requested in-person electronic exams with invigilation and highly secured testing environment to prevent cheating. Additionally, outlining the challenging hidden problems of evaluation in open and distance education universities, they proposed some solutions to reduce plagiarism in doing assignments.