Thank for the Disk Inventory X. I found out that windowserver_last.log is almost 15G, so I delete it. windowserver_last.log shows log file repeat over and over again. I have to check in the future when it bigger what cause it to be that huge. It is just a log file, so it should not be that big unless it keep repeat stuff right that. I suspect it is Neooffice 2.1 I install last night, but I have to check later. Thank for all the help.
