I am trying to upgrade my firmware to 4.0.1 on my iPhone 3g 3.1.2 but everytime I hold down shift and click restore select the ipsw file I get a error, check the picture below. The phone just has a usb cable then itunes symbol on top. And it just restarts! I don't get what I am doing wrong! Any help will be appreciated!

Originally Posted by JazzyStahh

I am trying to upgrade my firmware to 4.0.1 on my iPhone 3g 3.1.2 but everytime I hold down shift and click restore select the ipsw file I get a error, check the picture below. The phone just has a usb cable then itunes symbol on top. And it just restarts! I don't get what I am doing wrong! Any help will be appreciated!

Normal/expected behaviour - Apple has stopped signing iOS 4.0.1 - in fact they only sign iOS 4.2.1 (the most recent iOS version). The SHSH check on the 3G can be in theory bypassed, but you need to perform the restore without using iTunes (this is still something that is being developed, it's not ready yet)

Unless you can get access to a mac and can use Pwnagetool 4.1.2 or 4.1.3 to make a custom IPSW that prevents baseband update. I would strongly recommend you stay on iOS 3.1.2

Thread closed, this is not a problem, it is expected behaviour. Warnings about backing up SHSH with TinyUmbrella or Cydia to avoid this kind of problem have been around for 1.5 years now.