Chronic Dev Team had released greenpois0n to jailbreak iOS 4.2.1 for Windows foriPhone 4, iPhone 3GS, iPhone 3G, iPod Touch 4G,iPod Touch 3G and iPad few weeks back.

If you had trouble jailbreaking your iPhone,iPad or iPod touch using greenpois0n then here are some troubleshooting tips based on inputs from our fantastic readers that we hope will help you in successfully jailbreaking your iOS device.

Use the latest version of greenpois0n:

Chronic Dev team have been releasing new version of greenpois0n to fix issues. So ensure that you have downloaded the latest version of greenpois0n either from this page.

Step-by-Step Tutorials:

Mac and Windows users can follow our step-by-step guide to jailbreak their iOS devices on iOS 4.2.1 using greenpois0n.

Run as Administrator

If you’re a Windows XP user then try running greenpois0n as‘Administrator’ (right-click on the greenpois0n exe and select ‘Run as an Administrator’)

Disable Virus Protection And Firewall

If you’ve anti-virus or Firewall running in the background then please temporarily disable it. Some users have reported issues with BitDefender anti-virus.

Connect your iOS device directly to your Mac or PC

Connect your iPhone, iPad or iPod touch directly to your Mac or PC rather than via a USB hub.

Keep Holding the Home button:

After putting your iOS device in DFU mode, don’t release the Homebutton. Keep holding the Home button until greenpois0n informs you that the jailbreaking process is complete.

Ignore the Unable to Find gBdevList, fs_mount, fs_unmount, fs_load_file Errors:

If you see the following error message on the screen during the jailbreak process:

Unable to find gBdevList

Unable to find fs_mount Unable to find fs_unmountUnable to find fs_load_file

Ignore the errors and continue holding the Home button and wait for the jailbreak process to complete.

Cydia Option Missing in Loader App:

If you don’t see the Cydia option after launching the Loader app to install it then either keep trying by quitting and relaunching the Loader app again or using Redsn0w 0.9.6 RC8 (download link) to install Cydia by selecting the ‘Install Cydia’ from the options.

Clean Restore:

Greenpois0n recommends a clean restore so if the above tips don’t work then you can try to restore your iOS device if you desperately want a jailbreak as it is not ideal.

We hope one of these troubleshooting steps help you in successfully jailbreaking your iPhone.

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