That can be everything, knowing all you told. So there many possible solutions. Although it's possible there is no solution at all either.
1. Your PC. Try another one or a laptop.
2. Your WiFi. Try an Ethernet-cable instead.
3. The connection with your ISP, starting with the modem. Contact your ISP.
4. The server at the university. Try Dropbox or so and sent a link to your teacher if it turns out that you can read them yourself without any errors.
5. Send them during the night when everything is quiet.
Ok so i'm currently a student in quarantine, doing work from home.
For some reasons these last few weeks, my internet access has been very bad.
I uploaded severals word and pdf files to submit online on the university work network, for the teacher to get them.
But for some reason, once the work is uploaded online, it get corrupted. Like, you try to open it, it say that your file has been lost and that word or adobe cannont open it.
Can somehow elaborate a theory of why this issue occur please ?

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