Factory restore iPhone 4 after Jailbreak

[myronn]

Dear friends,

I bought a locked (AT&T) iPhone 4 with iOS 5.0.1 on it with BB 04.11.08. It was not activated and I did a tethered jailbreak using Redsn0w 0.9.9b8. Then I discovered that it is impossible (to date) to unlock 04.11.08 baseband and I just want to give this phone back. The problem is that "Restore" and "Check for Update" buttons are greyed out... How can I get this thing to do a factory restore so that it goes back to non activated mode?

I read that I need to use TinyUmbrella and uncheck the box "Set Hosts to Cydia on exit". I did that but the button "Restore" in iTunes 10.5.2 is grayed out and I can't do anything

Can anyone help me, please?

 

[myronn]

upd: I edited the hosts file and deleted all lines with gs.apple.com in them. Then I restarted iTunes. But both "Restore" and "Check for Update" buttons are still greyed out :/ Is it possible to somehow make a factory restore without using iTunes? I'm a bit confused now, don't really know what to do...

 

[myronn]

upd 2: solved with dfu mode! ))

 

[JunkyDog]

Try to get in DFU mode, and see if iTunes finds it, and then you can restore it, i hope..