Look for a indicating the software is still signed.
Apple only signs the latest version of iOS for public release. Once a new version comes out, Apple "closes the window" on older versions, meaning they stop sending SHSH blobs for them. 3utools Error Unable To Request Shsh
: If you are trying to downgrade to an older, unsigned version of iOS without having previously saved your own SHSH blobs, the request will fail by design. Look for a indicating the software is still signed
If Apple has stopped signing the iOS version you selected, or if 3uTools cannot reach the verification servers, the request fails. This triggers the "Unable to Request SHSH" error. Top Causes of the Error Selecting an unsigned, older iOS firmware. Unstable internet connections blocking Apple's servers. Outdated 3uTools software. Corrupted firmware (IPSW) file downloads. : If you are trying to downgrade to
In some rare cases, the error is insurmountable. You should stop trying if: