Invalid B-Tree Node Size Fix Issues.

I currently have the hard drive from my macbook hooked up to my desktop via usb. The macbook hard drive shows up in disk utility but not on the desktop. When I verify and repair I get an "invalid b-tree node size". As a result I have bought diskwarrior to fix this problem. However when I try to open diskwarrior it says "diskwarrior cannot currently be run from this disk because mac os x ignores ownership of some disks by default." So, how do I get diskwarrior running so that I can fix this "invalid b-tree node size" and recover the data from my macbook hard drive?

G'day and welcome to the forums.

When you purchase DW, if it came as a download, it is necessary to burn to a DVD or USB thumb drive and boot from that. You cannot run the program when booted from the hard drive.

Thanks for you help. It turned out it was as simple as running it out of the applications folder where I had installed it. I do however have a new problem now.

Now when I try to open diskwarrior it freezes while scanning for disks, and if I open diskwarrior first then attach the macbook hard drive I just get the spinning pinwheel.* So, my question is how do I get diskwarrior actually up and running and recognizing my macbook hard drive so that I can fix this "invalid b-tree node size" and recover the data?

As stated by Harry, Disk Warrior needs to be run separately from its own boot disk or thumb drive. Certain types of repairs such as the one you need to do can not be done by Disk Warrior while the hard drive in mounted.

Sorry, I'm not very computer literate but I'm trying to understand. So you're all saying there is no way to fix my macbook hard drive with diskwarrior by connecting it to my Mac Pro as an external hard drive? Based on my research it seems if I can just figure out a way to get diskwarrior to start up (without freezing) and recognize it I'll be able to rebuild it. Or at least attempt to rebuild it. Or do I need to wait till I get the diskwarrior disk put the hard drive back in my macbook and boot up off the diskwarrior disk?

Burn DW to a USB thumb drive and boot from that. Contact alsoft support if this does not appear on their forums. You did purchase direct froM Alsoft?