The first case is that there are typos or special characters in the file, so you need to check the contents of the email to see if there are any garbled words.

There is another route of transmission. When inserting a picture into an e-mail, you cannot delete or change the picture name and original path. So you need to put the pictures in a separate folder. The upload failure is mainly a system problem, but it may also be your problem. The first is the institutional issue. First, you don't need to upload papers on the campus network. If you use the external network to log in, there will be various bugs. Check whether it is a network problem. Second, you upload too many users and the website crashes. Try again next time. Third, there is something wrong with the website system. Contact the person in the network management center to solve it.

Then it's your own problem. You did not follow the format required to upload the paper. I suggest you check the upload requirements.