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My first jailbreak was using this program and on this firmware with my Iphone 4, hope you all enjoy.

To clear some things: This jailbreak support iphone 4 3GS 3G and ipod non-MC Model. This jailbreak is untethered for some idevices and tethered for some, heres the list:

Untethered
Iphone 3GS 3G and older ipod touch models
Tethered
4th generation devices (ipod touch 4th gen and iphone 4)

Tethered means that you have to connect the phone to your computer every time you turn it off or needs to reboot it you have to connect it to the computer.

These are the files you need:
Redsn0w 09.06.b4:
Windows: You must login or register to view this content.
Mac: You must login or register to view this content.
The 4.2.1 .ipsw firmware for your device: (you ONLY need the one for your device!)
Iphone 4: You must login or register to view this content.
Iphone 3GS: You must login or register to view this content.
Iphone 3G: You must login or register to view this content.
Ipod touch 4: You must login or register to view this content.
ipod touch 3G: You must login or register to view this content.
Ipod touch 2G: You must login or register to view this content.
Itunes 10.1 [go to apple.com and download]

1. Start itunes 10.1 and have it running in the background
2. Start Redsn0w
3. Hit browse and browse for your downloaded .ipsw file
4. Hit next and it will prepare the jailbreak
5. Select install Cydia and press next
6. This is a page that tells you to make sure your Idevice is plugged in and turned off
7. Now it's work time! Whene you press next you have to get ready and hold the power button for 3 seconds. After that press the home button without releasing the powerbutton and hold them both for 10 seconds. Thene release the power button but keep holding the home button for 15 seconds. The instructions also comes up on the screen. This is called putting your device in DFU-mode.
8. If done correctly Redsn0w will recognize your device and the jailbreak begins, go grabb a sandwich, and when you come back, you will have a jailbroken Idevice!

Notes:
If Cydia doesnt open, reboot your device and it will be working. If you have tethered jailbreak you will have to do these jailbreak steps again to boot up, but instead of checking "install Cydia" you check "just boot tethered now"
Check this thread to see good cydia apps: You must login or register to view this content.
If you want help, just pm me or write here!

Credits:
The iphone dev-team for Redsn0w 09.06.b4
You must login or register to view this content. for helping me with my jailbreak so I could help you and for the download links
Nathanx for his thread that contained cydia app list
Me, for writing this thread

Happy holidays <3

Isn't this still in beta? And anyways I just got 4.1 so I don't feel like downloading another update.

Umm. I do everything up to when you put your iPod Touch device into DFU Mode. I have an iPod Touch 4g 8g. I get through all the steps in Redsn0w until it like freezes at "uploading ramdisk." On my iPod i see Downloading Jailbreak Data. But on Redsn0w it gets stuck. Any suggestions?

Had that same issue when going to JB 4.1 on my iTouch 2g.

When you start redsn0w open up the task manager as well and find the process for redsnow.exe and click on it(but don't do anything yet). Once you entering DFU mode(preferably the last stage) go to that process you highlighted and then right click and Select Affinity and then check CPU 1 ONLY, so its the only thing checked.

Then you should no longer get stuck at the ram disk.

Hoped this helped!

Thanks, it helped! Done.

Yhea I think your right, but it works

To be honest, it doesn't really matter if it's tethered or not. I never turn off my iPod Touch, and the only time I reboot it is when i'm putting on a new theme, and that doesn't even effect the jailbreak.

Yep it's true, but if you want to reboot it for some reason your screwed

Nice guide! Im waiting for a JB that doesnt involve me re-downloading everything back though

It gets stuck on 'Exploiting with limera1n'... any ideas?