Ensure your Windows hosts file (located at C:\Windows\System32\drivers\etc\hosts ) does not have any lines containing "apple.com" that might redirect the connection.
If Apple has stopped signing a particular version of iOS, the request for an SHSH blob will fail. Causes of "Unable to Request SHSH" in 3uTools 3utools Error Unable To Request Shsh
Here’s a clear, professional message you can use to report or seek help for the "3uTools Error: Unable to Request SHSH": DFU Pro Flashing forces a deeper hardware-level handshake
Import your downloaded IPSW firmware file and click . DFU Pro Flashing forces a deeper hardware-level handshake which often overrides standard logic bugs. Summary Checklist for a Successful Flash This method doesn't rely on Apple's signing server
For certain older devices (like the iPhone 4, 4s, etc.), 3uTools has a built-in workaround. If it fails to query an SHSH, it may prompt you with a "forced downgrade" option. This method doesn't rely on Apple's signing server. You will also see the equivalent of this error in iTunes as , which has a similar set of potential causes.