The "Unable to request SHSH" error in 3uTools typically occurs around the during a flash or restore process. It generally signifies that 3uTools cannot verify the firmware's digital signature with Apple's servers. Common Causes
The is a rite of passage for iOS enthusiasts. While frustrating, it is almost never a fatal error. In 90% of cases, it simply means you are trying to install a firmware version Apple no longer approves of. 3utools Error Unable To Request Shsh