I've been having troubles with my external HDD and have been looking so hard for a solution.
I've tried everything. Diskutil, FSCK, testdisk. But only to find what I already know… "Invalid B-tree node size". It's unbelievable that Apple hasn't included a fixer for this kind of problem within its tools like diskutil.
My concern is, what is the meaning of this error?
Is there any solution to this problem without using a expensive 3rd party software?
Isn't there any open source software to recover my data?
Has anyone fixed this problem before?
I certainly would love just to buy a specialized software like DiskWarrior, but I can't afford that price.
Best Answer
It basically means the file can't be looked in the B-Tree. A more in-depth explanation can be found at https://www.easeus.com/mac-file-recovery/invalid-b-tree-node-size.html
Option 1 - Disk Utility
It's an inbuilt disk repair utility that repairs most commonly seen hard drive problems.
If Disk Utility can't repair your disk, run it again. Or else, move on the next solutions.
Option 2 - Fsck command
The fsck command is used to repair disk and file system problems on your Mac.
Option 3 - Reformat
Take the Mac hard drive reformatting as the last step, because this formatting process will erase all data on the drive completely. Make sure you've backed up your hard drive with Time Machine.
Disclaimer This answer is originally from https://www.easeus.com/mac-file-recovery/invalid-b-tree-node-size.html and was helpful for me when i had the same issue.