Make sure you copy the -entire- launch line into a single line. You are seeing that error as the line got broken into two parts; the first part starting with "/usr/bin/java", and the second with "jagexappletviewer". I suggest sticking it in a text file first(name it "runescape.sh"); makes things easier. Then you can just type: "cd *directory you put runescape.sh in*" "chmod +x runescape.sh" "./runescape.sh"