How many examination attempts do I have?
For each of your exams, you have four opportunities to take the exam. The last opportunity, in the case of non-immediate examinations (i.e., for lectures), is before an examination board. So, you are allowed to retake an exam three times, which equals four attempts in total. If you do not pass the exam on the fourth attempt, you will unfortunately be deregistered from your studies and barred from all programs (at the University of Vienna) that require passing that particular course.
However, there is an exception since October 1, 2022: For the final exam of your program, you will have an additional attempt, allowing you to take the exam a fifth time.