I have a spare iphone 3GS which my friend gave me and it has never been jailbroken before. I decided to save Blobs using Tinyumbrella and In the log file it shows 09/21/2011 15:13:06.578 iPhone3GS 4.1 (8B117) SHSH SUCCESSFULLY saved! I know i can't use Cydia to restore as it has never been jailbroken. Therefore i start TSS server and ensured that the host file contains 127.0.0.1 gs.apple.com #127.0.0.1 localhost #188.8.131.52 gs.apple.com 127.0.0.1 gs.apple.com I opened itunes, shift click restore and browse to iPhone2,1_4.1_8B117_Restore.ipsw. It returned error 20. When i tried restoring 4.3.5 it works. To prove that everything i have done is correct, i switched off my wireless internet beforehand. What could be wrong? Please help me.