Q: Another Error downloading

Today when I try to export any file ,final cut server shows me this:

Error downloading.
/Users/yangwz/Desktop/中国元素镜头/时光机器－雪山2.mov (No such file or directory)

but the original 雪山2.mov file exists in the hard disk and can be found.

I restored the latest backup,but it doesn't work. When I re-entered final cut server client ,the problem still existed.
Is there any one met this problem? And who can help me solve the problem? Thanks very very much