I have an iPhone 3G and I am trying to upgrade to iOS 4.2.1 but it keeps giving me errors (1604). I also tried using a custom firmware of 4.2.1 but that gave me the same errors. What can I do? I think I might need a custom firmware made from pwnage tool but I don't have a mac. Anybody help me out?

Originally Posted by camoj11

I have an iPhone 3G and I am trying to upgrade to iOS 4.2.1 but it keeps giving me errors (1604). I also tried using a custom firmware of 4.2.1 but that gave me the same errors. What can I do? I think I might need a custom firmware made from pwnage tool but I don't have a mac. Anybody help me out?

Error 1604

Device was not pwned (signature checks were not blocked). Custom firmware can't be restored until the device is pwned

You absolutely need to use a custom IPSW created with pwnagetool. We do not recommend or support sn0wbreeze or custom IPSWs created with sn0wbreeze.

What OS version are you running right now? TinyUmbrella can help you with this if you are stuck at the "slide for emergency" screen.

You can generally pwn your current iOS version with redsn0w (once you know what iOS version your iPhone is running and have picked the right redsn0w version and original IPSW)