there is no sim card installed in the iphone you are attempting to activate. please disconnect and insert a sim card in the iphone"

Well do as it asks and put a sim card into it. You can't activate a phone without a sim card.

Similar problem for me too. Ensured that my sim is already inserted. Don't know what to do next. Can anyone help? mine is 3GS phone.

Having the same problem. I've tried a different SIM card (one out of my other iPhone that works) and I've tried restoring, but neither worked.

Could it be that you rphone has been locked? is it jailbroken?

Not jailbroken, and it was working fine until the recent update.

Sometimes if a phone has been jailbroken and unlocked from a carrier and the iOS is updated it tends to lock the phone again

It's an AT&T phone but we have been using the H20 "pay as you go" SIM, which is AT&T network. We have two other iPhones working fine on the same plans. I guess it's possible it had been jaibroken before I got it, but I thought once a phone was jailbroken there was no going back. I had previously restored and updated it through itunes and my wife used it for a year with no issues.

Had been using the phone for almost a year after jailbroken. recently did OS upgrade using itunes. after restoration, i got this 'no sim' problem. don't know how to fix this. if i do jailbreak once again, will i lose all my data (especially photos)....

Problem solved! I opened it up to inspect the SIM pins and found a tiny broken piece of plastic from the SIM holder. Got it out of there and now it works again!

you opened up what the iphone?

Had this same problem since somewhere this summer with ipad 2:

no SIM or no simcard installed.

Was already desperate and had decided to check in with apple support.

Just read the post from madawkward.

Took a compressed air spray and sprayed into the sim tray and miraculously the sim is recognized again!

Hope this will be for keeps.

Thanks for the suggestion!

I tried all of the above. AT&T iPhone 3 was unlocked for T-Mobile. Now trying to upgrade to the latest available operating system to use it purely as a WIFI device for Spotify/Pandora. I obtained a brand new SIM card (unactivated) from the AT&T store, and it still says "no SIM card installed." Any updates available since the last post a year ago?

markjay10 wrote:

I tried all of the above. AT&T iPhone 3 was unlocked for T-Mobile.

How, exactly, was it unlocked?

If AT&T did not authorize unlocking it, then it was hacked, which explains why id doesn't work now.

Unauthorized unlock, as it was years ago before the "Apple factory unlock" was available. Do you know of any workaround? Really a pain to waste a perfect wifi device...

You can't get help here at all for your hacked phone. Sorry.