nawalg said:
Okayy thanks for the explannation. But i need to ask, what is DFU? I dun quite understand. Im sorry. Im new, i only know how to jailbreak. Heheh
DFU(DeviceFirmwarwUpdate) is a fail safe mode you can go into to restore should your device freeze, or just has problems, that cannot be resolved with reboots and stuff.
DFU mode is designed to be activated by physical button presses(regardless of software problems) that way...no matters how bad your device gets messed up....you will always be able to enter DFU mode so you can restore
There is only one way to enter DFU mode.
It is a series of physical button presses/holds.
How to enter DFU mode:
1) Shut down device *completely*.
2) now *simultaneously" press the sleep/power button and the home button...count to 10 as soon as buttons are pressed
3) As soon as you get to 10...release the sleep/power button...only(keep holding home button)
4) As soon as you let go of the sleep/power button...start counting to 15...and do not let go of the home button until you have counted to 15.
If you followed the steps correctly your device will be in DFU mode. The device has a black/blank screen...it just looks like it is shut off....but it's not...it's in DFU mode.
*NEVER* enter DFU mode while device is still on. Developers tell you to shut down device fully before entering DFU for a reason...so why not do things rite.
A lot of people will say its fine to enter DFU while device is on....but trust me...it is not. You risk not having processes stop properly before powering off. This in itself...can cause "invisible" problems.. #1 reason to always shut down fully (slide to power off) before entering DFU.
There is also PWNED DFU mode.
This is a little different.
PWNED DFU is a hacked version of regular DFU.
PWNED DFU mode is for restoring to custom iPSWs *only*. Besides restoring to a custom iPSW, there is no reason you should enter PWNED DFU mode.
You can only enter PWNED DFU mode with an exploit called Limera1n packed in a package called iREB. iREB is built within almost all jailbreak tools....sn0wbreeze, redsn0w, iFaith, and can be downloaded as a standalone app from here :
ih8sn0w.com
Only none-A5 devices can enter PWNED DFU mode...because it requires a bootrom exploit(hardware) and there is no boot level exploit for the 4S and iPad 2+ yet.
So only iPhone 4 and lower models can enter PWNED DFU mode.
How to enter PWNED DFU (so you can restore to a custom iPSW):
1) Open iREB(or tool that has iREB built in...which is basically all of them except Absinthe)
2) Plug in iDevice
3) enter DFU mode
4) wait for iREB to inject the Limera1n exploit
You are only in PWNED DFU if you get the success message from iREB.