I want a clean restore my 5.1.1 jb iphone 4s. But my Tiny Umbrella - Set Hosts to Cydia on Exit is grey out. So how am I going to uncheck it? I saw a lot people said uncheck the Set Hosts to Cydia on Exit. I tried restore from iTunes directly I keep getting error 21. So I unable to do the clean restore. Thanks in advance if anyone able to help.