Permission issues can prevent 3uTools from connecting properly to Apple’s servers.
Fix:
3uTools requires a stable connection to Apple's TSS (Tatsu Signing Server) servers. Aggressive antivirus software or Windows Firewall might identify the data transfer as suspicious and block the SHSH request. how to fix error unable to request shsh on 3utools when upd
Steps:
Before you try any technical fixes, do this first. Apple stops signing older iOS versions within 1–3 weeks of releasing a new one. Before you try any technical fixes, do this first
When an OS is "unsigned," Apple’s servers will reject every single SHSH request. 3uTools cannot fix this—it is a server-side lockdown. Before you try any technical fixes
If you saved your own SHSH blobs using TSS Saver or 3uTools before Apple stopped signing them, you can use the "Pro Flash" (Retain User’s Data) mode and manually load your .shsh2 file. Otherwise, move on.