Here is a video guide to help you to restore a Firmware on your iPhone or iPod Touch really simply.
All official Firmwares of Apple are available on the blog.



Required :

• iPhone or iPod Touch.
• iTunes 9
• Firmwares

Note that you will lose your jailbreak if you have it.

For NON-jailbroken iPhone

• Open iTunes

• Press on « Search for Updates » then iTunes will detect your Firmware and so, install the new one 

 

For jailbroken iPhone

Appuyer sur  » Shift » sur votre PC et cliquer en même temps sur le bouton « Restaurer ».

In case of crash, DO NOT PANIC :

• Shutdown your iPhone (press buttons HOME+POWER) and unplug it from your computer :

A pop-up of iTunes will appear and will ask you to search for new updates on the activation server : Accept and continue
iTunes detects then that you are in DFU mode and then Restore is beggining.

Don't forget to accept when Operator update is requesting.

- Restore old Firmware (iPhone 3G)

- Jailbreak Firmware

- Firmwares iPhone et iPod Touch