I have been trying for a full day now. I'm using Win7 Home Premium, iTunes 10.1, and the latest version of TU. I've saved my SHSH blobs for 4.0.1, turn off the firewall, I put the iPhone in restore mode, I started the TSS servers in TU, hit Shft+ restore in iTunes and select the 4.0.1 iOS. Error 1004 pulls up and stops the restore. When I try restoring the iPhone back to 4.2.1, it gives the same message. What can I do?