i have a friend with a ipod touch 3g 8 gigs. aka 2g mc model version 4.2.1 or 4.2 and to jailbreak it it would be easyer to downgrade so can i have some instructions of how to do that
iTunes connects to Apple's servers in order to obtain a necessary signature, known as an "SHSH." When Apple releases an update to iOS, the servers stop giving out SHSHs for older firmwares, preventing a restore/update to that firmware from occurring. so i assume you don't have your SHSH backed up... you need to wait for greenposi0n whichj should come out n the next few days.
To downgrade, you'll need to enter DFU Mode first. To put the iPod touch in DFU Mode, connect it to your computer and turn it off. Hold the Sleep and Home buttons for 10 seconds, then let go of the Sleep button. Keep the Home button down for ~20 more seconds. The screen should be off. Open up iTunes, and it'll tell you that the device is in recovery mode. Option-click (Mac) or Shift-click (Windows) the Restore button, and point it to the IPSW for iOS 4.1. @Dter ic: Apple's still signing 4.1 for the iPod touch 2G. (Don't know why, but they are.) Nevertheless, saving the SHSHs is still important, for when Apple decides to stop giving them out.
