Argh Ive been sitting with this problem now for several hours. I have a jailbreaked unlocked iPhone 3GS with iOS 4.0.2 with baseband 05.13.04 that I want to upgrade to iOS 5.1.1. Ive downloaded iOS 5.1.1 from here: http://www.redmondpie.com/download-...-4-3gs-ipad-ipod-touch-direct-official-links/, I then used redsn0w to keep the baseband (Im not sure if its neccessary, but I get the same problem even if I dont do it) When I try to upgrade it in itunes by using shift + update I always get the error: Unknown error occurred (11). Ive been googling for several hours without finding a solution, I thought I found the right solution here http://www.personalcomputerfixes.com/program-errors/itunes-error-11-fix-tutorial/ because the problem seemed exactly the same, but it didnt work either... I tried to put the phone in DFU mode by using redsn0w and then trying to upgrade using itunes, but when I start itunes when having the phone in DFU mode itunes says the phone has to be recovered before its possible to use it in itunes, I can therefore not press the upgrade button since its grayed out. Is this normal? It seems common for people to being able to upgrade when having the phone in DFU mode. What should I do?