Do not trust your memory. Always verify signing status externally.
A faulty USB cable or port is interrupting the data exchange. 3utools Error Unable To Request Shsh
3uTools relies on its own database of signed firmwares. If their local database hasn’t synced with Apple’s servers, it will think a firmware is signed when it isn’t. Do not trust your memory
If 3uTools misreads your ECID, you can enter it manually. 3uTools relies on its own database of signed firmwares
blobs are digital signatures that Apple uses to control the installation of iOS firmware. When you try to install or restore an iOS version via iTunes or 3uTools, your device sends a request to Apple’s servers (GSX). Apple checks if the firmware version you are trying to install is currently "signed" (approved) by them.
If "Easy Flash" fails, try putting your device into manually before clicking the Flash button. This puts the device in a more "receptive" state for server requests. 3uTools provides a guide on how to enter DFU mode specific to your device model. Conclusion