Shit! shit! Actually i didn't realize my PC is infected by Data.exe virus. Last time my PC infected by virus is about 2 years ago. Named virus brontok.exe. Last time AVG scan my hard disk, its about 3 days ago. Noticed no virus detected. But last night i print past year questions and look at these. There what I got. So i did realize that my PC infected by virus. So I tried to find it out and lastly I found Data.exe. Very unusual and difficult to find because this virus use different name while running on task manager. I have to find it in registry and lastly i found virus named data.exe. Now I have to reinstall new anti virus. Maybe Avast!