Try posting the output of pwd
. From the above output, I would guess you're in the directory /home/rob
. You want to be in the directory /home/rob/Desktop
Another thing you can do is just type the full path to the file you want to execute (but sooner or later you're going to have to learn to get around directories and stuff).
So to run the install script, try sh /home/rob/j2re-1_4_2-linux-i586-rpm.bin