This is a classic problem but I can't find the right solution for me. I have downloaded iOS 11.1.2 (current latest version is 11.2.1) from apple's official servers and tried to install it manually with the latest iTunes 12.7.2.58 on my iPhone 6. After extracting the software, I get the error:
Declined to authorize this image on this device for this user.
I'm currently on iOS 10.3.3 and don't want to upgrade to the latest version to keep my iPhone "jailbreakable".
I've tried to restore from my MacBook and my PC. The PC gave me error 3194 which seems to be the same error.
I know Apple doesn't sign this version anymore but I thought that upgrading was always possible (as opposed to downgrading). Am I wrong?
I checked my hosts files (/etc/hosts and /private/etc/hosts) and it looks fine. I also tried to restore in DFU mode without success.
Anyone with a potential solution is welcome to share it.
