I have been trying with little or no success to jailbreak and unlock my iPhone 2G. I’m using the instructions in iClarified to jailbreak on the 3.0.1 firmware. My iphone does not have an active SIM card, so to restore my iPhone I first must do a forced restore otherwise when I plug my iphone in iTunes it goes to the “Welcome to your new iPhone” screen and does not giving me the option to restore. This is the only step witch differs from the instructions. The problem I’m having is I get all the way to “Please wait while your device is being jailbroken” and then I get this message from my computer “One of the USB devices attached to this computer has malfunctioned, and window does not recognize it:” I’m don’t know what I’m doing wrong. Im using:
Redsn0w-win_0.8
iPhone2G GoldMaster Final iphone1,1_3.0_7A341 restore
Any suggestions?

What version of iTunes?

Sounds like a USB problem. Look at the section "USB Troubleshooting" on this page Update and restore alert messages on iPhone, iPad, and iPod touch

Also, you can use Redsn0w 0.9.2 to jailbreak iPhone OS 3.0 or 3.0.1 - instructions are pretty much the same. Could be worth a try.