Hi, I've just been given a 3GS off my dad (he's just got the iPhone 4) which was previously JB'd at 3.1.3 using Sn0wbreeze (SHSH on file for 3.1.3 only) I wanted to upgrade to 4, so i found some custom ipsw's on the web. I tried to use these, but it kept hanging and failing during the restore process. Anyway, i thought it might be a good idea to upgrade to the stock firmware first - what a mistake that has turned out to be! Now whenever i try to restore to th custom firmware i get error 1600. Is there any way of jailbreaking the phone now or is it going to be non-jailbreakable? JUST TO CONFIRM - IT IS DEFINITELY A MB MODEL! Thanks in advance guys Curtis EDIT: I just realized this is in the wrong forum - it was intended to go into the JB forum - can a mod please move it?