Open book exam tomorrow but the file with the questions are open to everyone already I was going through the files on canvas of my course, then I saw a file called like Examination_(coursename)_2021 and was like &quot;it's probably the practice&quot;. I opened it and it seemed like the actual exam, so I sent a message to course group like is this the actual exam? It seems like it is and they asked me to share it with them, which I did. Then I started thinking I should tell my professor that I have access to the questions. I also checked if other people in my class could find the file which they did. So now I'm kind of lost, obviously, I want to do well on the exam but also I don't feel good about it. Although the exam is tomorrow and it is an open book exam, I feel like I should tell my professor just because now my mind isn't focused on the exam at all, I feel I am morally obligated to tell them. Though I would have to tell everyone in my group that I told the professor which I don't think they would be happy about because I asked them if I should tell the professor and they already said no. Another reason I'm worried is that the professor might be able to see when I first viewed the questions, which was a day before, I'm just so lost about what I should do.
Edit:
I think I will tell my professor. However, now I don't know if I should tell the people in my class or just keep it anonymous. I'm worried that if I don't tell my class, some people will only have prepared for the questions and not for the actual course. I definitely regret sharing the exam with the people in my class now, it would've been much easier to have told my professor, if I hadn't shared the questions with the people in my class.
Edit 2:
So I did send an email yesterday and apparently, it was just a past exam from another year. So it's all good. I just completed the actual exam today and feel quite good about it. Thank you to everyone who helped give advice!!
Tell your professor.  I don't know whether Canvas keeps logs such as you describe, but it doesn't make any difference.  Your feeling of moral obligation is correct. You are obligated to tell your professor.
Here is some general advice.  Author John D. MacDonald has one of his characters say, approximately, &quot;In the case of any ethical decision, the thing you least want to do is probably the right choice.&quot;  (Quoted from memory, which is why it's approximate.  I think Benedict De Spinoza wrote something similar.)