This may be a strange request, especially considering how old this phone is. I'm attempting to jailbreak a 3GS that is on 4.2.1. I've tried using Redsn0w with a 4.2.1 firmware. Here's where it goes wrong: this is an AT&T phone with no sim card. It cannot be unlocked after turning on (can't view the about in the settings and get accurate information), all it says is a SIM card is needed for activation. I follow the steps to a tee on Redsn0w and each time it comes back almost immediately with an unexpected error. I don't really know where else to go on this, any guru's out there that can help? If there is any additional information needed I'll provide it the best I can. Help please?