applyweb系统上传pdf如何preview

如题，本人在申请umich还有gatech上传成绩单之后都预览不了，今天提交推荐信，点击preview也看不了，浏览器提示：

This browser is not compatible with Flash. Please use a modern browser such as IE10, Chrome, Safari or Firefox, or make sure to update
to the latest Flash version

求问大家都是如何解决的