I have itunes 7.5 now and try iclarified's guide, but it doesn't work, can anyone shred some light here?

The iphone could not be restored. An unknown error occured (20)

I am on a iphone 1st generation and using windows, but I also have a Mac.

try to find a itunes 7.6.2 an retry the same way there must be 1 error 1015, itunes can not downgrade the baseband, but after downgrad to 1.1.4 you must erase the bb and restore your phone to 1.1.4

http://sleepers.net/news/?page_id=216

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IPHONE DEV TEAM ARE THE ORIGINAL

I'm having this exact same issue right now. I've tried iTunes 7.6.2, and i've been trying with iTunes 7.5, and i'm getting the same error every time.

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Week 37 iPhone
- 1.1.4 [Unlocked/Activated/Jailbroken] -- T-Mobile USA

which one 1015 or 20

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IPHONE DEV TEAM ARE THE ORIGINAL

Error 20.

I got the phone into DFU, but it wouldn't let me downgrade at all, and now it wasn't letting me out of DFU... so basically i'm reupdating to 7.7, fixing 2.0 using the restore button, then i'm going to start all over again.

I'll post my results when i break something again :hack:

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Week 37 iPhone
- 1.1.4 [Unlocked/Activated/Jailbroken] -- T-Mobile USA

I tried with 7.4, 7.5, and 7.6. All same result error 20, now I am trying on a Mac in stead

Hi there...

I've got the same until I realise that many people, including me, mistake "Restore Mode" for "DFU Mode".

If you are getting error 20 (Version you are trying to load is older than the one you already have) check if you are really on DFU.

A lot of people seem to think that DFU mod and Recovery mode on the iPhone are the same. Apart from the blank screen in DFU mode and the iTunes/Dock Cable logo this is another, greater difference.

When you put your phone in Recovery mode the iPhone still loads up a mac "OS" if you will. Whereas in DFU mode the iPhone does not load up the OS. This means that communication between the iPhone and iTunes in DFU mode is minimal - therefore iTunes will not randomly decide to interrupt you while downgrading firmware etc.

To put your phone in recovery mode simply:

1. Switch off the iPhone.
2. Hold the home button as you connect your iPhone to your PC/Mac.
3. Continue to hold the home button untill you see the iTunes/Dock Cable logo.


To put your iPhone in to DFU mode:

1. Turn on iPhone
2. Connect to PC/Mac
3. Open iTunes
4. Hold down power and home buttons
5. Wait untill red slider appears to shut down iPhone - keep holding the buttons.
6.Wait untill the iPhone shuts down
7. Release power button, keep home button pressed (if the Apple logo appeared you didn't release the power button quick enough - try again!)
8. Wait about 7 seconds - iTunes should say there is an iPhone connected in "restore mode"

Tried that also using both ibrickr og iliberty to get me into DFU still error 20.

I also tried Mac now and same result

You need DFU mode to downgrade with iTunes 7.5
Run iTunes, connect iphone to pc.
Hold power+home exactly 10 seconds - iphone will shutdown and its screen will remain black (with is very important that you dont see apple logo!!! if you see apple logo - try again)
After 10 seconds release power button, but keep holding home.
Release home when you see a message from iTunes.

If you get 16XX Error you just need a new version of Apple Mobile Device Support.
You can get this package from software update , choosing "install and keep package" when updating iTunes to 7.7 (Pkg will be located in Downloads/iTunes [Leo])

If you get 1015 Error - all OK. downgrade baseband and restore 114 again - after unlock with any software.