I am running 4.3.5 and I just updated my phone on accident, and I have a T-mobile. Whenever I connect my phone to iTunes, it says the SIM card is invalid. I can't go on my phone, and there is a slider that says,"Slide for emergency".
Here I talk about one way to unlock your iPhone 3G with no SIM.
OK then, open iTunes application on your computer. If it is not updated to the latest version, then update it. Now connect USB data cable for iPhone. Press the round button which is at the bottom of the screen and slide your finger as instructed for unlocking your iPhone screen.
Then press the “settings” logo on the iPhone and then press the “General” option, and press the “about” option to make note of the version number of your iPhone OS (operating system). After that download Blackra1n jailbreak utility from this site. You can see many versions but download the version you found before. Then open the application Blackkra1n from your computer a small box will pop up, click , “make it ra1n ; click OK ; wait for a few minutes, your iPhone will restart. Now press the blackra1n icon on your iPhone screen.
You need an Internet to pass to the next step ; select the “Cydia” and “snow” packages on your iPhone. Wait while it downloads and install these end after that restart the computer again.
