Invalid SIM on iPhone 3GS

unbubblelivable · Oct 18, 2011

I restored and updated my iPhone 3GS to iOS 5 and I receive the "invalid SIM card" error. I replaced the SIM card and AT&T ensured me that wasn't the issue. I haven't jailbroken my phone, but I hear that may be the only solution? I'm stuck at the "invalid SIM card" screen though can go back to the "Restore" screen, but those are my only 2 options. Therefore, I'm unable to find out what the firmware is or any other details. Please be very descriptive with the steps for possible solutions!
Thank you in advance!

Jmills87 · Oct 19, 2011

If it says invalid SIM and you are on a factory firmware then it's definitely an issue with the SIM.

unbubblelivable · Oct 19, 2011

I've tried 2 different SIM cards though and that didn't fix it. Would unlocking/jailbreaking fix it? If so, how would I go about doing that?

Jmills87 · Oct 19, 2011

No, if its an official SIM and it's not working on a factory firmware, it's definitely not going to work on a jailbroken firmware. There's no need to unlock if you have an official carrier.