HELP! How to do with this strange 0 size file?

Hi, I bought an Inspiron 600m laptop just recently. I wanted to install a Chinese-English dictionary online, but when I was installing I realized that it showed some characters I can not read at all, then I cancel it. I didn't realize there is one more file before I used Norton AntiVirus and AntiSpam to scan my whole system and no any abnormal was detected.

 

But I found that there was a strange file on my Desktop then. :smileysurprised:That file name is CA89W5C7. I can not open it, read it, modify it, move it and delete it by any method at all. when I do something to it, it pops up "Cannot read from the source file or disk" But its file size shows zero. So I don't know what kind of a file it is (no extension name) and how to delete it. All system seems work normally and not influenced by that file. But it looks not good if there is such a file on my Desktop. So I want to ask why do I suddenly have this strange file and what should I do to delete it. Thanks!