[ame]http://www.youtube.com/watch?v=Cj9JK1gMPQc[/ame]

This video will show you how to Jailbreak iOS 4.2.1. I have added some troubleshooting tips and have attempted Greenpois0n multiple times using this method. It worked for me, so as long as you follow the steps very carefully, you should be okay.

Supported iDevices:

- iPod Touch 2G (all bootroms)
- iPod Touch 3G
- iPod Touch 4G
- iPad 1G
- iPhone 3Gs (all bootroms)
- iPhone 4
- iPhone 4 Verizon (_not_tested_)
- AppleTV 2

Make Sure:
- Your Device is restored to 4.2.1 CLEAN DFU (except those preserving baseband)
- You have Greenpois0n from the official source or one of the mirrors below
- Anything that blocks connections in or out should be turned off or allowed for Greenpois0n (like Little Snitch)
- You have internet connection

Other things:
- My phone was activated with an AT&T Sim card
- Sync'd to a new profile on iTunes

Steps:
1. Restart your Mac
2. Plug in your iDevice after your Mac has restarted
3. Kill iTunes if it opens
4. Open Greenpois0n RC5 2
5. Hit Jailbreak and get ready
6. Follow the on screen instructions for DFU mode, make sure you do them on time!
7. CONTINUE HOLDING THE HOME BUTTON UNTIL YOU SEE SCROLLING TEXT!
8. You should be Jailbroken with the Loader app on your homescreen
9. Open up Redsn0w
10. Find your 4.2.1 iPSW
11. Click Next
12. Check mark INSTALL CYDIA
13. Contine the steps of Redsn0w
14. Your device will reboot and now your are Jailbroken on 4.2.1 with Cydia!

Things You Need:
- Greenpois0n Read Me(just to read): #1527535 - Pastie
- Greenpois0n RC5 2 *UPDATED*:
greenpois0n OSX RC5 2.zip (mirror)
Download greenpois0n OSX RC5 2.zip from Sendspace.com - send big files the easy way (mirror)
- Redsn0w &4.2.1 Firmware: iPhone Downloads
- www.Greenpois0n.com (OFFICIAL)

PC please?

Is this for mac computers only? Where are the steps to follow for a regular PC? Im just finally glad untethered jailbrake is finally here...i have old jailbrake stuff i need to clear out to make room for more memory. When i updated to 4.2.1, the jailbrake stuff still in my ipad but unaccessable. Plus i need IfILES back for file management ;-) n ill get to play all my emulators again. Plus i missed winterboard themes sooo much..lol

Not available for PC yet, only Mac.

Dude I tried on my iPhone first. Found loader but no Cydia. Tried to restore almost killed my iPhone 4 and had apple store revive it. Should I try again? This one or redsnow?

Originally Posted by ZibaWal

Dude I tried on my iPhone first. Found loader but no Cydia. Tried to restore almost killed my iPhone 4 and had apple store revive it. Should I try again? This one or redsnow?

From what I am reading, jailbreak with green poison RC5 and then install cydia with redsnow.

Will this work with an OSX VM?

Originally Posted by blac2k8cs

From what I am reading, jailbreak with green poison RC5 and then install cydia with redsnow.

Would you mind elaborate on this and any links? I would experiment on my i phone 4 before iPad

Originally Posted by blac2k8cs

From what I am reading, jailbreak with green poison RC5 and then install cydia with redsnow.

I jailbroke my iPad yesterday and had no real issues. I used green poison only. I did have to go through the loader process several times before I got to the Cydia launch, however. Be patient as it works well when completed. Very stable

I also installed intelliscreen as I have it on my iPhone and it says it will work on the iPad. Beware, it's does not and will give you problems.

Great apps to get.
Display out. Fantastic to bring all iPad apps and functions to any large monitor
Multiflow

intelliscreen works fine for me 4.2.1