You downloaded the wrong IPSW file for your specific device model. Proven Solutions to Fix the Error 1. Update 3uTools to the Latest Version
: Apple stops "signing" older iOS versions after a new release. If you are trying to install an unsigned firmware, the SHSH request will fail. error unable to request shsh 3utools 9 updated
A corrupted cache forces erroneous requests. You downloaded the wrong IPSW file for your
Press the , type notepad.exe , right-click it, and select Run as Administrator . If you are trying to install an unsigned
: Ensure you have a stable internet connection to reach Apple's servers and use an original or high-quality lightning cable. Why This Happens with iOS 9
This is the most common and significant cause of the error. When attempting to downgrade to an older iOS version that Apple has stopped signing, 3uTools cannot obtain a valid SHSH blob, resulting in the error at 9%. .