Downgrading iPhone 4 from iOS 5 to 4.3.5 (Error 1604)

[robinenrique]

I upgraded my iphone from 4.3.3 to iOS 5 Beta 6 just to give it a try (as a developer), however I prefer version 4.3.3, I am aware that downgrading from iOS 5 to 4.3.3 is almost impossible unless I have my SHSH blob (which I don't) so I'm trying to downgrade to 4.3.5 instead. I put my iPhone in DFU mode and restore it but it gets stuck on Preparing iPhone to restore and after 5 - 10 min it gives me an error 1604. I tried downgrading my iTunes to 4.1 and 3.1 and it doesn't work with either. What can I do?

Thanks

[Simon]

Have you tried it on another computer?

[shitmix]

Absolutely the same problem, step by step. The only exception is that i have saved SHSH files all the way from 4.3.1 to 4.3.5

And I still can restore to iOS 5 beta 6.

[Simon]

Absolutely the same problem, step by step. The only exception is that i have saved SHSH files all the way from 4.3.1 to 4.3.5

In that case you can try entering pwned DFU and restoring to a custom 4.3.3 made with pwnage tool or snowbreeze.

[robinenrique]

I read somewhere that could be the issue, I haven't tried it in another computer yet, but why could that be the problem? I'm trying it today though.

[Simon]

I read somewhere that could be the issue, I haven't tried it in another computer yet, but why could that be the problem? I'm trying it today though.

TBH that error is a weird one. Not quite sure what causes it but most times people have success getting around it by using another computer or uninstalling itunes completely and reinstalling it.

[shitmix]

In that case you can try entering pwned DFU and restoring to a custom 4.3.3 made with pwnage tool or snowbreeze.

Thanks for the advice. I'll give it a try and will share the result. I have never tried a custom IPSW though - I hope that I will be able to put a stock one in the future...

I forgot to mention, but maybe it is important - I'm trying all this since iOS 5 crashed and put my iPhone into recovery mode.
I'm restoring back to iOS 5 beta 6 and will try to downgrade from this state.

[robinenrique]

I will try it in another computer and tell you about it, but I'm pretty sure it won't work , I tried uninstalling iTunes three times and even downgraded it without success.. I will let you know if it works.

Another question, assuming it does work, would I downgrade basebands as well doing so?

[Simon]

On a iPhone 4 yes your baseband will be downgraded back to the 4.3.5 baseband (4.10.01 I believe).

At least as long as Apple is still signing 4.3.5

[robinenrique]

TBH that error is a weird one. Not quite sure what causes it but most times people have success getting around it by using another computer or uninstalling itunes completely and reinstalling it.

Tried in another computer and didn't work.

I'm getting pretty tired of this, any other ideas?

[iJasonTATE]

I had this issue about a week ago with my iPad and downgrading from iOS 5 b6 to 4.3.3 (with blobs). This is a bit of a different scenario than yours but I got the same error, 1604. So all I did was downloaded iTunes 10.3 and I restored fine back to 4.3.3. I see that you have already tried downgrading your iTunes without success. This is a very interesting case. I'm going to do some research.

-Jason

[robinenrique]

I had this issue about a week ago with my iPad and downgrading from iOS 5 b6 to 4.3.3 (with blobs). This is a bit of a different scenario than yours but I got the same error, 1604. So all I did was downloaded iTunes 10.3 and I restored fine back to 4.3.3. I see that you have already tried downgrading your iTunes without success. This is a very interesting case. I'm going to do some research.

-Jason

Yes. Things I've tried so far:

(I am right now in a recovery loop)

- Tried with iTunes 5.0, 4.1 and 3.1 without success.
- Tried with another computer, tried with another user account and disabled firewalls.
- Killed iTunes process on task manager once the error was shown and re run iTunes. (read it somewhere)

All that I've left to try out is to restore without shift + restore on iTunes (updating with iTunes directly) and to run the update directly from windows folder (AppData - Apple iPhone Update, but I can't find it anywhere in windows 7)

[iJasonTATE]

On Windows XP :
Documents and Settings\<User>\Application Data\Apple Computer\iTunes\iPhone Software Updates

On Windows Vista/Windows 7:
Users\<User>\AppData\Roaming\Apple Computer\iTunes\iPhone Software Updates

On Mac:
~/Library/iTunes/iPhone Software Updates

This were the folders should be located on Windows XP, Vista, 7, and Mac OS X. Hope this helps.

-Jason

[robinenrique]

On Windows XP :
Documents and Settings\<User>\Application Data\Apple Computer\iTunes\iPhone Software Updates

On Windows Vista/Windows 7:
Users\<User>\AppData\Roaming\Apple Computer\iTunes\iPhone Software Updates

On Mac:
~/Library/iTunes/iPhone Software Updates

This were the folders should be located on Windows XP, Vista, 7, and Mac OS X. Hope this helps.

-Jason

Thanks Jason,

Found the folder but there isn't any iPhone Software Updates available in it.

I'm trying to download it directly from iTunes and restore it without shift + restore, I don't know if that could make any difference, I guess not.

Another thing, I had my AT&T sim card the whole time, I don't know it that could make any difference at all. Can't try it right now, though, cause I'm downloading the update from iTunes

[iJasonTATE]

Okay, let me know how it goes after the update completes.

-Jason

[robinenrique]

Okay, let me know how it goes after the update completes.

-Jason

Didn't work. I can restore to iOS 5 without any problems, but can't restore to 4.3.5. Still getting error 1604.

[iYeow]

When you restore to 4.3.5, did you put your iphone into dfu mode ?

[iJasonTATE]

When you restore to 4.3.5, did you put your iphone into dfu mode ?

He did and e is still receiving this error from iTunes.

[iYeow]

I have a feeling it has something to do with the itunes version. Itunes 10.2 should be the one for 4.3.5 restore. Error 1604 also means it cannot verify its blob.

[robinenrique]

Do I need blob for 4.3.5?

I will try with iTunes 10.2, I'm also going to downgrade first to iOS 5 Beta 1 and then downgrade to 4.3.5 to see if its possible..

Also, everytime I restore to iOS 5 Beta 6 and then try to downgrade to 4.3.5 I get into a recovery mode loop..