Hi All, I have a Macbook Pro that I bought in late 2009, which I upgraded to the latest version of Snow Leopard, and all of a sudden it would only boot up from my bootcamp partition (running win XP). I booted from my OS X 10.5 install disk (can't find my SL disk) and ran Disk Utility first aid on the Mac partition (the main one I use) and it gave me the invalid B-tree node size error. I bought the latest version of Disk Warrior 4.3 but my MBP would not boot from the DVD, so I installed OS X 10.5 on a USB flash drive and booted from that and installed DW on it. I ran DW and it repaired the directory such that I could browse/access my files on the corrupted partition, but I still cannot boot from that partition. If I try to boot from it (it shows up as "EFI Boot" when holding the option key at startup), I get the Prohibitory sign instead of the Apple sign at the grey boot screen, which I've read means that critical system files are not in place. I noticed that there is a "Rescued Items" folder that DW created in the root directory and within it there are about 50 "Missing Folders", some of which contain what seem to be system files. My guess is that this is the reason I cannot boot from my "repaired" partition. Ultimately I am trying to avoid copying all my files from the corrupted partition, buying another copy of snow leopard, and starting from scratch. Is there any way you think I could do that or is this a lost cause? I would really appreciate any advice/info you all would be willing to provide. Thank you!