This guide will show you how to Unlock and Jailbreak your iPhone 2G using redsn0w 0.8
Things you will need.
Once you have downloaded everything, extract redsn0w-win_0.8.zip
to a location on your computer. You should see redsn0w.exe
Find your iPhone 2G 3.0 firmware file you downloaded earlier. Select it and click Open.
RedSn0w tells you that the ISPW is successfully identified. Click Next.
There will be a quick pop up.
Select your options to Install Cydia and Unlock. If you don't need to unlock your iPhone 2G you can de-secelct Unlock
If you are unlocking you need to locate the 3.9 and 4.6 bootloader .bin files you downloaded earlier.
Now that you have told RedSn0w where the bootloader files are click Next.
At this point you should make sure your iPhone 2G is plugged into your computer AND turned off. Click Next.
RedSn0w gives you instructions. We are entering DFU mode now. First hold the power button for 3 seconds.
Keep holding the power button and start holding the home button for 10 seconds.
Release the power button but continue holding the home button for 30 seconds.
RedSn0w does its thing.
Finally after RedSn0w has finished loading everything onto your phone you will see the screen below. Don't mess with your phone while all this is going on because your phone is still being Unlocked and Jailbroken. After your phone restarts you are done!
If you have any issues/questions please post them in the Jailbreaking Forum