now i got problem, can pls help me..my phone stuck at recovery mode...

i want to upgrade from 4.3.2 to 4.3.3...
mine already got shsh 4.3.3 saved however during restore i always get the 1013 error...
try to fix it using lot of solution however the problem still the same during halfway restore..
already 1 day pening google and try lots of solution...

can somebody help 

I'm getting error restoring to ios 4.3.5
stuck in infinite recover loop

I think you should
- download tinyumbrella
- start TSS Server
- Run iTunes
- DFU iphone
- Shift-Click Restore
- Choose ipsw
- ALso edit your host file... google it and see how

See how?? Just a theory...

bro...
done all above already...
still the same...

Try to use this to kick out of recovery mode.

if all iphone user know what is shsh blob its easier...

guys, can i use update from 4.2.1 to 4.3.3 ? I download the IPSW and pres SHIFT+Update, will that works?

You won't be able to unless you have the shsh saved.

mine already saved everything but error 1013 appeared...now stucked 

OK, first, is your iPhone factory unlocked?
And what is the version of your current (before upgrade) modem firmware? (baseband)
Cause when we upgrading to iOS4.3+ there will be a baseband checking.
Last time when I upgrade from 4.1 to 4.3.3, I did not check the option "Update iPhone 4 Baseband" in TinyUmbrella, it will cause an infinite recovery loop.
But make sure your device is factory unlocked version before doing this.

You can now try (if your device is FACTORY UNLOCKED):
1) Connect your device to PC.
2) Put your device in DFU mode. (Press and hold the Home button and the Power button at the same time for 10 seconds, then release Power button but keep pressing Home button for another 15 seconds, you'll see nothing on screen)
3) Start TinyUmbrella, click Start TSS Server (check the Update iPhone 4 Baseband setting).
4) Open iTunes, iTunes will prompt you there's a device in DFU mode needed to be restored.
5) Shift+Restore and select the iOS 4.3.3 ISPW file you had downloaded earlier.
6) Wait and should be done without problem.

Downgrading (4.3.5 to 4.3.3) or upgrading (4.1, 4.2.1 to 4.3.3) or restoring (4.3.3 to 4.3.3) requires you to have the 4.3.3 SHSH saved (either during the time Apple was still signing them via TinyUmbrella) or if Cydia has automatically saved them (which it doesn't do that often so manually save them via TinyUmbrella)

For a guide on how to use TinyUmbrella to downgrade (the guide for upgrade/restore) to a firmware that Apple no longer signs (REMEMBER, you need to have YOUR SHSH already saved!!!), follow the steps as posted in iClarified.com Guide on Downgrading your iPhone Firmware using TinyUmbrella

If you enter an infinite recovery loop, you may need to run fixrecovery (follow the guide as well as it does gives you the link for downloading fixrecovery and the necessary zlib.dll files)

Usually, 1013 error is related to the host file (usually) but without touching your host file (i.e setting your host file to point either to the local server 127.0.0.1 gs.apple.com) you cannot get the downgrade working.

This is my recommendation

1. If you have SHSH saved in Cydia, I would save it locally
2. I would edit the host file to have this line 127.0.0.1 gs.apple.com
3. I would run TU and make sure I have the TSS Server running.

This usually works for me, BUT, I haven't had to downgrade in a loooong time since I NEVER make the mistake of stupidly updating my iPhone. The last time I did it was for my friend when I wanted to upgrade his 3Gs to 4.2.1, other than that it's been a while.

Guys it worked!Thanks a lot...

I combined the info given from both of u... really thanks 
What i did:
1) check the ''iphone 4 baseband'' checkbox in TU...
2) TU TSS Server running
3)delete the 127.0.0.1 gs.apple line in host file in the windows>system32>driver>etc>hosts..
4) manually restore by pointed 4.3.3 ipsw in DFU mode
5) completed and successfully restored to 4.3.3 

Appreciated and many thanks on ur help!now can jailbreakme alredy 

Excellent news!, I'll remember next time to ensure I tick the Update iPhone 4 Baseband box. All of my downgrading work were done on the 3Gs, I have not had the opportunity (nor do i intend to have that opportunity) to do a downgrade/upgrade of the iPhone 4 ...

It's not a must to tick the update baseband box, just that if left unchecked, the restore will ended up infinite recovery loop, and you need to use certain tools to kick out of recovery (I used Fix Recovery at that time)
And after kick out of recovery, I notice my iPhone 4 iOS had upgraded to 4.3.3, but baseband remained at the one used in 4.1, which caused a problem that the signal bar would show 1 bar all the time (due to iOS version and Baseband version mismatch). So I decided to re-restore and update the baseband since my iPhone 4 is officially unlocked.

Provided you have 4.3.3 shsh blob.

Can someone stop encouraging upgrade/downgrade without mentioning shsh blob.