Help Needed-Iphone 4 restore itune error 1601 or 1602

[akv0403]

Background-
Recently I got the factory unlock confirmation from at&t for my jailbroken locked Iphone 4 (ios 5.0.1 & BB 4.11.08). I connected it to itunes and got the message that "Congratulations Your Iphone Is Unlocked" , earlier the itune was not detecting my iphone. Per the at&t email , I was following the steps to complete the unlocking process but got the error 21. While reviewing this forum I come to know that I should put the device in DFU mode . I did that now , while restoring the iphone , I am getting error 1601. I have tried everything available on google result .
- I have uninstalled the itunes many times - (searched and deleted everything from apple) , still getting 1601 or 1602.
- Changed the uSB port
- Restarted

There are many tutorials available to for IREB and Redsn0w for custom IPSW.Since, I do not have custom IPSW (or I am not sure 100% about this) I do not think it is of my use.

My confusion is - As of now I wanted to take default factory settings with latest ios 5.1.1. What steps should I follow to fix the error 1601/1602 and get my iphone restored on 5.1.1 with default factory setting. I am not worried to preserve anything here data,BB,jailbreak ,application etc. I am new to iphone and got this as a gift from my cousin from US , but using it as ipod for the last 3 months . Please help me to fix this issue ... Please !

 

[akv0403]

Fixed...1601

hank you everyone for sharing the fix idea's... You all are corrrect one of the other solution did work for

someone However... after spending 6-8 hrs...I did not get fix even after applying all these idea's.... my bad luck

but it should have worked for other's....So I think there are many solutions for this error....

What helped me is a 10 sec trick I found on other blog..

Fix --

Iphone should be in DFU mode ( Google to know 'HOW')
Goto --
My Computer --> C Drive--> Windows --> System32-->Drivers-->Etc--> Host File

-Cut (remove) this host file and past it on desktop.
-Now comeback to itunes - provided you have fresh itune installation after removing it COMPLETELY from your system

(Ref- http://support.apple.com/kb/HT1923?viewlocale=en_US).
-Plug in your iphone to your windows via active USB port (no hub) and with good internet connection.
- Repeat the restore process and avoid doing multitasking ( I was lil careful... ).. And that worked for me

...restoring took max 10 min's.
- Once the restoring process is done , follow the instructions and complete the ragistration process. restart your

iphone and its on Factory default settings EnJOY !

- Put the HOST file back to its original path.

Remember - My iphone was jailbroken on 5.0.1/4.11.08 and recently got unlocked from at&t .

Hope this will fix your iphone toooo...

Keep helping ...!!!

Thanks everyone again!