my problem is this I have an iphone 4s unlocked with turbo sim telcel mexico company , the problem is that if I upgraded to System 7 iso as 5.1 and had had the app I could not install the same version of but in doing so I left in the activation of the white screen , I have taken the turbo sim and I entered the sim (which is orange Dominican Republic ) and I recognize it even makes me sign and everything but give to turn tells me that the sim is not allowed Ect . Ect . but when I do the turbo sim tells me there has been enabled by the server is not available then you try . not to do as they have told me the problem if the turbo sim is for version 5.1 and not for 7.1 and others have told me that it is possible that this reported in apple so I can not change which is false because I checked my IMEI all part and tells me it's okay .