I have iphone 4 version 4.2.1 with modem firmware 03.10.01 locked for AT&T I jailbreaked it successfully but i couldn't unlcok the carrier. moreover, I tryed to downgrade it but I should have SHSH saved with tinyumbrella-4.21.11 software where it is not available with me and i couldn't downgrade it.
I want to now if there is a way to downgrade the version with out saved SHSH an unlcok my iphone.
I want to now if there is a way to downgrade the version with out saved SHSH an unlcok my iphone.