iPhone 3GS upgrade

[kvijay]

Hello Friends,

I have a iPhone 3GS (16 GB) and would like to upgrade it to IOS 4

Following are my current iphone details.

Version : 3.1.2
Model : MC135LL
Modem Firmware 05.11.07

My phone is already Jailbroken & unlocked by Blackra1n and Cyidia.

Need your help were i can refer step-by-step guide to upgrade my iphone to IOS 4.

Best Regards,
Vijay

[eyeRobot]

iClarified - iPhone - How to Jailbreak Your iPhone 3GS Using PwnageTool (Mac) [4.1]

[kvijay]

iClarified - iPhone - How to Jailbreak Your iPhone 3GS Using PwnageTool (Mac) [4.1]

Thanks for your reply.

As i have windows XP this tool will not work for me.

Please suggest me an alternative.

Regards,
Vijay

[eyeRobot]

Get the latest version of redsnow from Dev-Team Blog

Use redsnow to only put your phone into dfu mode.

Check your private messages in 5 mins, a link may magically appear for you to download a custom firmware. Would you need hacktivation or do you have an original carrier sim?

...... Both links may have appeared. Just download the one you need.