1. Check your network connection: Make sure your network connection is normal. You can try reloading the page or using another network connection.

2. Use a supported browser: Make sure that the browser you use supports the latest version of the website. Sometimes, older browsers may not be able to load or upload files normally.

3. File format and size: Make sure that the file you upload meets the file format and size restrictions required by Shandong University Summer Camp. Usually, the website will specify the file types and the maximum file size that are allowed to upload.

4. Clear the cache and cookies: Try to clear the browser cache and cookies and reload the page. Caching and Cookie problems can lead to page loading or file uploading problems.