I am helping a friend with his MacBook Pro which will not boot. First I should note that I am not proficient with Apple computers. The computer turn on to and show the Apple logo and spinning wheel, nothing further. I have tried to boot in safe mode (shift pressed at startup). The additionally displays a progress bar that disappears at approximately the 30-40% mark but continue to display the Apple logo and spinning wheel. I have performed a Reset NVRAM (Option-Command-P-R). Nothing displayed, but reboot in 5-10 seconds. Turning it on while holding the Option key displays a HD icon labeled SnowLeopard and a button with an arrow. Clicking the arrow again displays the Apple logo and spinning wheel. I can boot in single user mode (Command-S) and get to a command line. LS shows me files and folders OK. FSCK -F runs for about 90 seconds checking and terminate with the message: The volume "SnowLeopard appears to be OK". Pressing D or Command-R does nothing Using verbose startup halts for sometime at "AppleYukon2: RxRingSize <= .....", but continues. Then shows 2 lines: "BootCacheControl: could not create temporary playlist file: No such file or directory" "BootCacheControl: could not write playlist" Lastly I tried chmod -R -N /Volumes, but get message "chmod: Failed to clear ACL on file /Volumes: Read-only file system" The original CD with operating system is not available.