Post: GreenPois0n RC5 Untethered Jailbreak for iOS 4.2.1 Released!
02-04-2011, 03:55 AM #1
moiz41510
Vault dweller
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Chronic Dev Team has finally announced that they have released the long awaited GreenPois0n RC5. It brings untethered iOS 4.2.1 jailbreak for all iOS devices and you do not need to have '4.2b3' SHSH blobs saved in Cydia, unlike the Redsn0w 0.9.7.

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Note: Make sure you have restored to official iOS 4.2.1 through 'iTunes' before attempting this JB.

Warning: If you are currently using iPhone with unofficial carrier and rely on an unlock please do not update to iOS 4.2.1, doing so will upgrade your baseband and making it merely impossible to unlock.Before continuing remember to back up your iPhone's 4.2.1 SHSH Blobs

Step 1: Download Greenpois0n RC5 for Mac [You must login or register to view this content.] or for Windows [You must login or register to view this content.].

Step 2: Once downloaded, unzip it and run Greenpois0n.

Step 3: Connect your iPhone via USB to your computer and click on “Prepare to Jailbreak (DFU)”

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Step 4: Now you will be prompted to put the device in DFU mode with on screen instructions to guide you.
1)Press and hold the sleep button for 2 seconds
2)Continue holding sleep; press and hold home for 10 seconds.
3)Release sleep button; continue holding home for 15 seconds.

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Step 5: Your device is now in DFU mode and should be ready for jailbreak. Click on “Jailbreak” to inject the exploit.

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Step 6: Once your iPhone, iPad or iPod touch reboots, it should be successfully jailbroken on iOS 4.2.1. Now start “Loader” located on the homescreen and install Cydia.

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Congratulation! You are now jailbroken on iOS 4.2.1!
You must login or register to view this content. GreenPois0n RC5 for Windows[You must login or register to view this content.]
You must login or register to view this content. GreenPois0n RC5 for MAC[ You must login or register to view this content.][You must login or register to view this content.]
You must login or register to view this content. iOS 4.2.1 for iDevices

Sources: twitter, redmondpie, You must login or register to view this content., You must login or register to view this content. (I added more details)

Facing Some Problems?
This is from a blog I write for ~ CoveringWeb.com

1st problem: stuck on “Greenpois0n initialized”
This one is the most easier problem, just run the new version of GreenPois0n known as RC5_2 by running the same guide posted here as we've already changed the download mirrors.

2nd problem: Greenpois0n loader crashed
Greenpois0n loader will only work when its official site works well. The site is often down because of 500,000 hits at the first night. If the site still not working, you can just follow the below steps:
STEP 1: Switch off your iOS device and run Redsn0w 0.9.7b6.
STEP 2: Select your firmware and just check on ‘Install Cydia’ option then complete the instructions to install Cydia.

3rd problem: Greenpois0n results by “FAILED” Error
Follow the steps below to solve this problem:
STEP 1: Connect your iOS device and run Greenpois0n RC5_2.
STEP 2: Open the TERMINAL, type in ‘cd Desktop’ (without quotes) and press Enter.
STEP 3: Now type in open Greenpois0n.app/Contents/MacOS/greenpois0n and press Enter. It will result in a new window and Greenpois0n will be started.
STEP 4: Follow the self explanatory instructions to put your device in DFU mode. The jailbreak process will start.
STEP 5: After it is jailbroken, a greenpois0n Loader will be there now. This is to let you install Cydia.

4th problem: Your device stuck on DFU mode after jailbroken
In this case, you have to leave your iOS device as it is for almost 2 minutes. Now press and keep on holding the home and power button simultaneously for almost 10 to 15 seconds until your device boots normally.

5th problem: Unable to find fs_mount, fs_unmount, fs_load_file Errors
Your iOS device must be ‘Switched Off’ when you connect, otherwise these errors will come.
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The following 2 users say thank you to moiz41510 for this useful post:

Storm, XxAKASHIxX
02-04-2011, 11:41 AM #2
cgs18
The Old NGU iDevice Guru
Originally posted by moiz41510 View Post
Chronic Dev Team has finally announced that they have released the long awaited GreenPois0n RC5. It brings untethered iOS 4.2.1 jailbreak for all iOS devices and you do not need to have '4.2b3' SHSH blobs saved in Cydia, unlike the Redsn0w 0.9.7. Keep in mind, the software is only available for Mac. A Windows version will be coming soon.

You must login or register to view this content.


Note: Make sure you have restored to official iOS 4.2.1 through 'iTunes' before attempting this JB.

Warning: If you are currently using iPhone with unofficial carrier and rely on an unlock please do not update to iOS 4.2.1, doing so will upgrade your baseband and making it merely impossible to unlock.

Step 1: Download Greenpois0n RC5 for Mac [You must login or register to view this content.].

Step 2: Once downloaded, unzip it and run Greenpois0n.

Step 3: Connect your iPhone via USB to your computer and click on “Prepare to Jailbreak (DFU)”

You must login or register to view this content.

Step 4: Now you will be prompted to put the device in DFU mode with on screen instructions to guide you.
1)Press and hold the sleep button for 2 seconds
2)Continue holding sleep; press and hold home for 10 seconds.
3)Release sleep button; continue holding home for 15 seconds.

You must login or register to view this content.

Step 5: Your device is now in DFU mode and should be ready for jailbreak. Click on “Jailbreak” to inject the exploit.

You must login or register to view this content.

Step 6: Once your iPhone, iPad or iPod touch reboots, it should be successfully jailbroken on iOS 4.2.1. Now start “Loader” located on the homescreen and install Cydia.

You must login or register to view this content.

Congratulation! You are now jailbroken on iOS 4.2.1!

You must login or register to view this content. GreenPois0n RC5 [You must login or register to view this content.][You must login or register to view this content.]
You must login or register to view this content. iOS 4.2.1 for iDevices

Sources: twitter, redmondpie, You must login or register to view this content., You must login or register to view this content. (I added more details)


It doesn't really work yet... Nd I already posted this....
02-05-2011, 10:27 PM #3
moiz41510
Vault dweller
Originally posted by cgs18 View Post
It doesn't really work yet... Nd I already posted this....


it does work, and my bad man. i just saw it
02-05-2011, 10:29 PM #4
italianboss
☆Level 1 Trustworthy☆
Originally posted by moiz41510 View Post
Chronic Dev Team has finally announced that they have released the long awaited GreenPois0n RC5. It brings untethered iOS 4.2.1 jailbreak for all iOS devices and you do not need to have '4.2b3' SHSH blobs saved in Cydia, unlike the Redsn0w 0.9.7. Keep in mind, the software is only available for Mac. A Windows version will be coming soon.

You must login or register to view this content.


Note: Make sure you have restored to official iOS 4.2.1 through 'iTunes' before attempting this JB.

Warning: If you are currently using iPhone with unofficial carrier and rely on an unlock please do not update to iOS 4.2.1, doing so will upgrade your baseband and making it merely impossible to unlock.

Step 1: Download Greenpois0n RC5 for Mac [You must login or register to view this content.].

Step 2: Once downloaded, unzip it and run Greenpois0n.

Step 3: Connect your iPhone via USB to your computer and click on “Prepare to Jailbreak (DFU)”

You must login or register to view this content.

Step 4: Now you will be prompted to put the device in DFU mode with on screen instructions to guide you.
1)Press and hold the sleep button for 2 seconds
2)Continue holding sleep; press and hold home for 10 seconds.
3)Release sleep button; continue holding home for 15 seconds.

You must login or register to view this content.

Step 5: Your device is now in DFU mode and should be ready for jailbreak. Click on “Jailbreak” to inject the exploit.

You must login or register to view this content.

Step 6: Once your iPhone, iPad or iPod touch reboots, it should be successfully jailbroken on iOS 4.2.1. Now start “Loader” located on the homescreen and install Cydia.

You must login or register to view this content.

Congratulation! You are now jailbroken on iOS 4.2.1!

You must login or register to view this content. GreenPois0n RC5 [You must login or register to view this content.][You must login or register to view this content.]
You must login or register to view this content. iOS 4.2.1 for iDevices

Sources: twitter, redmondpie, You must login or register to view this content., You must login or register to view this content. (I added more details)


already been posted
plz use the search button
02-05-2011, 10:30 PM #5
moiz41510
Vault dweller
Originally posted by italianboss View Post
already been posted
plz use the search button


mines a bit more detailed, dnt you think?
02-05-2011, 10:54 PM #6
cgs18
The Old NGU iDevice Guru
Originally posted by moiz41510 View Post
it does work, and my bad man. i just saw it


When GreenPoison was 1st released it didn't work or if u got it 2 work it would rarely work 100% but since then it has been updated nd fixed... nd ur post is more of a Tutorisl mines just kinda updates on everything To do with greenpoison

The following user thanked cgs18 for this useful post:

moiz41510
02-06-2011, 07:49 AM #7
Thanks for the guide. Probably going to try this once the servers are a bit faster.
02-06-2011, 10:18 PM #8
moiz41510
Vault dweller
ight, tell me if you need any help
02-07-2011, 12:39 AM #9
aVengeiV
aKa KernelMods
How do you delete this off of your iphone?
02-09-2011, 03:29 PM #10
I was using redsn0w.
Then ran this over the top to get it untethered.
works good Smile

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