As you know, it is currently impossible to restore a device to 4.0 or 4.0.1 without having saved its ECID.
But then how are all the people, going on vacation for example, going to upgrade their devices from firmware 3.0 to firmware 4.0 / 4.0.1.
Indeed, JailbreakMe having been released on August 1st, they stayed in 3.1.x jailbroken so as to be quiet.
Here is a tutorial written by a reader, cebe6seven, allowing you to upgrade your device from firmware 3.x to firmware 4.0 / 4.0.1.
- A device in 3.x
- The firmware 4.0.1 of your device (here)
- TinyUmbrella (here)
Connect your device to the computer and launch TinyUmbrella.
Check the “advanced options” box and save the ECID of your device version by clicking on “save my shsh”. A few seconds later, a message will appear: “succefully saved shsh”.
Then make a backup of ECID 4.0.1 like this: in “device / version”, select the firmware 4.0.1 corresponding to your device. (For example: iPhone 3GS 4.0.1 (8A306)).
Then click on “save my shsh”.
Put your device in DFU mode, launch Itunes and click on “start tss server” in tinyumbrella. As soon as the message “tss accepting connection” appears, go to the next step.
(Info. To go to DFU, it’s here)
Finally, in iTunes, restore your device with the firmware that you downloaded in the prerequisites.
Go to the tab of your device under iTunes, and hold down the “ctrl” key on your keyboard. Then click on the button [restaurer] in iTunes and choose the downloaded firmware.
Go to the tab of your device under iTunes, and hold the “alt” key on your keyboard. Then click on the button [restaurer] in iTunes and choose the downloaded firmware.
You should therefore be able to restore your device to 4.0 / 4.0.1 without worries 😉
Thanks again to cebe6seven for sending us the tutorial 😉