Having a little issue since I can't start my Mac Pro pretty annoying since I have lots of stuff both work as well as private related files on that machine.. I have a 1. generation Mac Pro never ever experienced any problem with that machine. Recently I ran out of space on my hard disks and then I bought 4 new 1 TB disks from Seagate - all the same model (ST31000340NS) I removed my older and smaller disk and configured the new disks like this: Bay 1: Boot disk, 1 partion on 1TB Bay 2: 2 partions on 500B each for file storage Bay 3: RAID 0 Bay 4: RAID 0 This morning when I wanted to start up my mac the process ended up with my desktop wallpaper showing up but I was not able to do a thing (keyboard not function) The only thing that is happening is the mouse cursor going into wait status (this multicolored wheel appearing) I can move the mouse arond on the desktop but nothing the program bar wil not come up if I put the cursor on the bottom of the screen. All my desktop icons are also gone. I have tried to reboot everal times with no luck. Fortunately, I have a mac book so I have tried to get access to the boot disk via a firewire cabel. When connecting via firewire I only get access to 3 out of 4 disks - the one I do not get access to is the bootdisk If I open disk utility (DU) and try to verify and repair the boot disk I get this: Show details output: Invalid node structure The volume OSX was found corrupt and needs to be repaired Error Disk Utility can't repair this disk…disk, and restore your backed-up files. stop dialogue box: Disk Utility stopped repairing "disk1s2" Disk Utility can't repair this disk. Back up as many of your file as possible, reformat the disk, and restore your backed-up files. Mhhh pretty much the disk that is physically damaged (some how) Then I read a bit on the internet about recovery features in Lion and found out that Command + R could help me. But when I try this my Mac Pro stops end up in loop where it can't boot into the desktop - it just ends up with the grey screen with an apple in the middle ad this flash like symbol going around beneath.. The I thought I might try to boot from my Snow leopard cd and see i I get more options like first aid and such but I only end up in DU having the same problems as above.. By now I'm pretty lost and would love a piece of good advice? I wonder how I can; "Disk Utility can't repair this disk. Back up as many of your file as possible, reformat the disk, and restore your backed-up files." How can I backup my files on that disk when i can't get access to it? And know I have to reformat the disc from DU but then All my files will be lost, so I have to backup or take an image of the disk before I format. That's my story, first time in 4 years (after I jumped on the mac-train) I experience a problem with my mac Just want to add, the bootdisk emits a noise that I have not heard before, it's not really loud but it's there just like it's doing something without being able to stop. Normally you can hear the disk spinning but this sound is like permanent not spinning but just a noise I hve'nt heard before from a disk By the way, if I hold down the option key whenn rebooting I get the screen showing I have this "Recovery HD" but how can i activate it? My boot disk also shows up next to it. If I click the recovery HD then the mac gets stuck with the grey apple screen. I just tried to insert my old boot disk with Snow Leopard installed so I could see if my system is working, and yes everything works good, of course not the boot disk with Lion installed..Since I have a USB docking station for hard disks I tried this as well. And by surprise the Lion disk now shows up on the snow leopard desktop as a ext. USB drive woow what a breakthrough! When I try to browse the disk i can see the basic file structure: Application folder which is emty Library folder also emty System folder opens up into second level (Library) and all the folders here are then emty Users folder 2 folders inside the shared folder and then my personal profile, both are emty Now I'm even more confused - any suggestions?