Hi Ayman, here are the installation steps I followed under mac osx 10.6.3 to solve the "bus error" message I got: - Open a terminal and type open .profile - If the file opens, just followed the instructions in the manual - if you get an error message saying that the file does not exist, you have to create it. - open a text editor and copy paste the lines below (assuming that you install OpenSim under /Developer/OpenSIm202/) : # shell variables PS1="\n$PS1 " PS2=": " # environment variables export DYLD_LIBRARY_PATH=/Developer/OpenSim202/sdk/lib/ # the path is initially set to "/bin:/sbin:/usr/bin:/usr/sbin" export PATH=$PATH:/usr/local/bin:/usr/local/mysql/bin export PATH=$PATH:/Developer/OpenSim202/bin/ # aliases - save the file with .profile as name, under your user directory - restart the terminal, OpenSim should now work... Hope that helps Guillaume