My Macbook's System partition is corrupt and won't boot or even mount. I originally thought I could boot from an external drive and copy over the files I need but since the partition won't mount from disk utility I doubt anything as simple will be possible. My next thought is to install a new system on an external drive and work on the corrupt volume from there. Is anyone familiar with a utility that might let me recover data in known folders? Mostly PSD files. The drive itself tests ok and the recovery partition boots. Possibly the problem is due to a volume optimization I did a week or so ago, but the machine seemed ok and even faster after. Before the partition quit mounting TTPro found volume structure errors, as did disk utility. Anything I can do myself or should I get a data recovery pro?