There are similar lines of questioning in the forum, but few valid responses. Apologies for reposting. I've searched for hours on end...
I'm a tech consultant (software, not hw) helping my relative out with a problem on MBP 2011 running Mavericks.
One day - it failed to startup & he was brought to diagnostics / language page. Disk Utility verify sees problems with Invalid Node Tree size. Repair says it can't be repaired.
fsck tried from single-user mode, nothing. I don't even know if fsck will work on a volume that is not mounted?
I tried creating a mount point (mkdir /Volumes/newmount) and mounting the drive there, no luck. Mounting from Disk Util also fails.
I tried creating an image of the drive (actually...all 3 of the drives...Mavericks I guess has an EFI and 'Restore' partition). The image failed to mount on an external HD.
I have purchased DiskWarrior - that's my next step. The last backup was "in August" which actually meant "June of 2012" upon investigation into his TimeMachine backups. He's got family / baby photos and videos and is desperate to recover.
Is there a way to remedy the 'Invalid Node Tree' issue? For instance, if I run migration assistant & migrate the volumes from old to new, will a new 'Node Tree' be created for me on the new HD? Is there a different approach I can take to making the disk image copy - just isolating the 'Macintosh HD' to improve my results?