How to downgrade or preserve the firmware of your iPhone

Yes, that is the exact FW I downloaded to my Mac. Does it matter if the phone has to be off before starting DFU?

I don't understand why I'm getting that message...

 

Its the same file name for the 3G and 3GS so you couls still have the wrong one. Delete the one you've got and download the one in the link I gave you. It's the official one from apple. Are you positive it's a 3G and not a 3GS?

If it's a 3G then there really shouldn't be a problem providing you are using the correct firmware. I don't think you even need to enter DFU. I can't remember the button you need to hold for mac but on windows all you need to do is hold down shift and press restore. Then you can show iTunes the ipsw file. It's the same process for mac but you hold a different button...

 

I deleted the first saved firmware and downloaded the one you provided to me. I am still getting the same error message. I even tried the process without putting the device into DFU...and it is a 3G.

I give up. lol

 

Well if your certian it's a 3G then I'm not sure why it's saying that.

The only thing I can suggest is to upgrade to 4.2.1 normally via iTunes then downgrade to 4.0.1...

 

hi does this work on 4.3?

 

Can you be more specific?

It works for any firmware you have SHSH's backed up for...

 

I upgraded from 4.0.1 to 4.3.2 preserving my baseband of 01.59.00 because I rely on unlocks as it's not a factory unlocked iPhone 4.
now am really hating this new iOS, the battery life has become so less, the battery drains out really fast. Tried everything for the past two months but no use.
I now want to downgrade back to 4.0.1 but my SHSH is only saved up to : 4.1, 4.2.1, 4.3.2 and 4.3.3. Is there anyway I can go back to 4.0.1 ? if not then I don't think I should have problems with 4.1 either as didn't hear much complains about it. For me 4.0.1 never had any problems.
what's worrying me from downgrading to 4.1 is will it change my baseband to that of the 4.1 ? because if my baseband changes to anything other than 01.59.00 it would mean I can't unlock and that would mean I can't unlock... that be wasting $700 which I can't afford.

 

There is no way that you can downgrade to 4.0.1 so far as you've never saved any shsh for that firmware, but yes you can downgrade to 4.1 and the simple process of downgrading using itunes will not change your baseband, you can also use tools like snowbreeze or pwnage tool (depending on what conputer you have) to preserve your baseband before downgrade.

 

As bab has already said you can't downgrade to a firmware that you don't have SHSH's saved for. To keep the same baseband so you can unlock you will need to create a custom ipsw using the tools bab listed. Do not downgrade using an official firmware or you will loose the ability to unlock...

 

Thanks for the help.
So can I follow the steps on this video without worrying about changing my baseband?
Okay so I can't actually put the link up in my post but if you search 'downgrade iOS 4.3' on YouTube, the first video that comes from the search result is the one am asking about
And also how can I be notified via email or another way that someone replied on the thread I posted at?
Thanks a lot!

 

Use a tool like snowbreeze if you are on widows computer or pwnage if you are on mac to preserve your baseband.
What about checking your account settings for receiving notification for threads that you have subscribe to?

 

Here's the video I think I should follow the steps from. You think this method one will let me preserve my baseband while downgrading?

[ame=http://www.youtube.com/watch?v=6d4Vk2MVAew&feature=relmfu]YouTube - ‪Downgrade iOS 4.3/4.3.1/4.3.2/4.3.3 To 4.2.1, 4.1 Firmware On iPhone, iPod Touch & iPad‬‏[/ame]

 

Let me see that video, i will post back soon.

 

That video isn't bad. He explaine everything quiet clearly and you might follow his advices to downgrade as well. Just remeber to have th computer admin, and itunes up to date and that you have really and perfectely save the shsh for the iOS you want to downgrade now.
IMO if you meet all those requirements, you are good to go.

 

Thanks a lot! I'll give it a try by weekend and let you know if it worked out well. It's just the baseband issue that's been worrying me.
Here's a screen shot of the SHSH saved in my iPhone.
and what iOS will you recommend other than 4.3.2 ? for me 4.0.1 worked really good. Didn't try any other iOS after upgrading from 4.0.1 to 4.3.2