If something irregular happened (like that restart) it's possible an old file was sent. Changing contents during copy should be impossible.
We had an exam at school. The professor downloaded our files onto her USB then uploaded them at home for marking.
The file that she showed me afterwards did not look like my finished file. Some steps that I had completed were not there. I don't know if it's possible that she took some unfinished file that I was unaware of, and did not take the correct finished file (the computer froze and had to restart during the exam). It did not even have the correct file name. I was not consulted for the download and all files were immediately erased afterwards so I have nothing to refer to.
Is it possible that something could have happened to the file when it was moved from one computer to the other? My professor says that that is not possible, that computers don't just erase or rearrange data, etc.
But something strange had occured last semester during a test for another class. I created a document, uploaded it to the school site, then when the professor printed it, it looked nothing like the document. It was the same one, with my name on it, but things had been deleted and formatting had been lost. We referred to the original upload, reprinted it, and it printed just fine the second time.
Could something like that have happened to my exam file? Or is the file she is showing me now 100% guaranteed to be the file I completed in class?
Thanks so much for any insight!

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