Thank Troy and Connie for the `positive' 'negative' answers toward other solutions instead of reinstallation. I will do that. Actually before asking those questions, I have already educated myself that I will do this before Christmas. One thing that makes me really sorry for doing this is that there had been many people in this mailing list encourging me to use x86_64 Linux instead of i386 Linux. Best regards, Kuo Kan LIANG Division of Mechanics, Research Center for Applied Sciences, Academia Sinica, Taiwan