As many of the jailbreak softwares for the iPhone use iTunes to flash the iPhone, there is a higher likelihood of errors occurring. If you’re unlucky, you’ll discover an error message after you try to restore your iPhone with custom software. Different errors have different error codes, but the most common is that you didn’t put your iPhone into DFU mode properly when going through the hacking/jailbreaking procedure.

Timing is essential when putting your iPhone into this mode, as even half a second off the exact count can result in your iPhone being in recovery mode (characterised by the iTunes and cable logo on your iPhone screen) versus DFU mode (which results in a completely black screen).

If you’ve already got a custom IPSW file (the backup you create with your jailbreak software such as Pwnage Tool or WinPwn), you can put your iPhone into DFU mode by watching this YouTube clip and restoring the custom IPSW through iTunes.

Future iPhone Updates
Once you’ve gone through the entire ordeal of hacking your iPhone, you don’t want to unknowingly revert it back to the Apple-authorised software. If new iPhone software becomes available, do not download it until a new version of the jailbreaking software goes online – usually only a few days after the Apple software update is released. You’ll then have to go through the whole jailbreak procedure again.