I know that the news is likely to be bad but here is hoping that I will get some feedback about "what next" in terms of what is possible if not possible to mount with a fix of some sort.
I have a Western Digital My Book 500GB Firewire/eSATA/USB 2 Studio Edition external hard drive which is daisy-chained with 7 other hard drives, mostly WD and one Lacie which is the only drive to not mount.
I have done all the checks in that I have disconnected it from the daisy chain and followed the prescribed start up by unplugging, waiting, plugging it into direct power socket, pressing the rear button (also tried it with not pressing it), then plugging in Firewire/USB cables (in turn of course) into the drive and then only into the freshly restarted MacBook Pro (which is also mains connected) running OSX10.6.8.
Nothing will make the drive mount.
Replaced it into the daisy-chain, tried again with full power-cycle of the entire chain, they boot up as expected, the unmounted one remains visible in Disk Utility, checks out fine, repairs fine (since there is nothing TO repair) and still will not mount.
Unlike most (but not all) it has an Apple Partition Map, not a Master Boot Record or GUID Partition Table, if that is even relevant. The other (WD) drive with the same partition map is fine.
Now having done my research I am very disheartened to note that it is likely to be a lost cause.
I cannot afford to lose the data on there. It contains 480GB+ of film data which I was in the process of "mirroring" (but since I have 6TB of data to mirror that is a big task and I was working in strict order and only upto 5 with this one being 9 in a set of 13...) and I am keen to learn what I can possibly do to rescue this terrible situation.
Can I use firmware to "fix" its unmountability? Can I send it somewhere to have the data extracted? Can such data even be accessed, given that Disk Utility can see the drive but cannot "see" the files contained therein?
Please and thank you.