Make sure files can be uploaded
If OneDrive is struggling with a file, make sure it’s supported. For example, OneDrive is unable to upload files that are larger than 20GB. If it’s larger than that, consider putting it in a ZIP file to make it smaller. Also, make sure the filename isn’t too long, since that can confuse OneDrive, too. If the entire file path, including the file name, exceeds 400 characters, it won’t upload.