are digital signatures Apple uses to verify the firmware you are installing.
Apple only "signs" the most recent versions of iOS. Once a new version is released, they stop signing the old one within a few weeks. i unable to request shsh 3utools fix install
I can give you a specific for your exact device. are digital signatures Apple uses to verify the
3uTools must connect to Apple’s TSS servers to request the SHSH blobs. If your connection is blocked, the request will time out. I can give you a specific for your exact device
If you are trying to downgrade to an older iOS version (e.g., iOS 15 to iOS 14) and you manually save SHSH blobs while that version was still signed, there is currently no way to fix this error. No software, including 3uTools, can "force" Apple to sign old firmware once the window has closed. To help you get this sorted, could you tell me: What model of iPhone/iPad are you using? Which iOS version are you trying to install?
You must select a version that is currently being signed (indicated by a green icon or "Available"). 2. Update 3uTools to the Latest Version