Everybody knows that Mac OS X 10.5.6 “breaks” PwnageTool where the DFU mode won’t work. Fortunately the iPhone Dev Team posted a note on this issue and offers a work-around. Unfortunately they didn’t tell us how to rebuild kext cache.

I read about the bug (yah, it’s just a bug, and not Apple’s attempt to mess up jailbreaking) but I upgraded my Mac OS X anyway, thinking I don’t need to jailbreak my devices. How wrong I was! A friend brought in a sick iPod touch and seeked my help. Oh well, a friend in need is a pest indeed. Suddenly I regretted upgrading my OS. When I attempted to Option+Restore, I get “An unknown error occured (21).” and could not proceed. So sad.

So I re-read the team’s notes and now detail below the exact steps I took to fix the “bug”:

Oh, needless to say (but I’m saying it) … you can try it at your own risk, but it works for me.

1. Quit all running apps except for Safari/Firefox.
2. Disconnect your iPhone/iPod, and un-mount all your USB devices such as harddisk and flash drive, leaving only your USB keyboard & mouse connected (duh).
3. Download Mac OS X 10.5.5 combo update from here.
4. Mount the .dmg and you should see the MacOSXUPDCombo10.5.5.pkg file inside.
5. Drag and drop the .pkg into Pacifist. (You can download Pacifist from here.)
6. Click on right-pointed triangle icons until you are at the following folder:
   /System/Library/Extensions/IOUSBFamily.kext/Contents/PlugIns/
7. Select the “AppleUSBHub.kext” file.
8. Click on the “Extract To…” icon on Pacifist’s menu.
9. Choose to extract it to your Desktop.
10. Confirm the extraction with Administrator Privileges (and enter your pw when prompted.)
11. Repeat steps 7 to 10 to select and extract the “IOUSBCompositeDriver.kext” file.
12. Go to Finder and select “Go to folder …” from the “Go” menu.
13. Copy and paste the following path into the text field:
    /System/Library/Extensions/IOUSBFamily.kext/Contents/PlugIns/
14. A new Finder window pops up after you click the “Go” button. You will see lots of .kext files.
15. Back up “AppleUSBHub.kext” and “IOUSBCompositeDriver.kext” by copying them to your “Documents” folder (or wherever you like).
16. Drag and drop the two files you extracted earlier from your Desktop to the new Finder window, replacing the existing copies. You will be asked to autheticate. Authenticate by clicking the button and enter your password.
17. Once again, go to Finder and select “Go to folder …” from the “Go” menu.
18. This time type “/System/Library/” (without quotes) in the text field, and click “Go”.
19. Look for a file named “Extensions.mkext”.
20. Autheticate and delete the said file (be careful; do not delete the “Extensions” folder; delete the “Extensions.kext” file!)
21. Launch your Terminal app (it’s in your /Applications/Utilities/ folder.)
22. Copy and paste the following terminal command into it:
    sudo kextcache -k /System/Library/Extensions
23. Hit the Return key to execute the command. You will be prompted to enter your password.
24. You must reboot your Mac immediately once the terminal command has been executed successfully.
25. Done.

Related Posts:

1. PwnageTool 2.0.3 is Out, but it Doesn’t Work!
2. PwnageTool 2.0.2 is Out!
3. Downgrade Mac OS X iTunes 7.6 to 7.5, Really
4. Growl Notifications for Amule
5. Mount and use your iPod touch as a Thumb Drive!