Apple released a number of updates for its iOS products this week. It seeded the second beta for iOS 5.1 to developers, Apple TV 4.4.4, and a small iPhone 4S update.

The latter release was strange because it wasn’t available to everyone (just those on iOS 5.0 or lower), and the version number didn’t change. So, what was it for?

Some folks speculated that Apple tweaked iOS 5.0.1 to prep for its international iPhone launch this weekend, but now there’s another theory. AppleInsider points to a support page that recently surfaced on Apple’s website which seems to completely explain the update.

The above resolution page is for the SIM card errors that some iPhone 4S users have been reporting over the last few months. The issue causes popup messages like “Invalid SIM” or “No SIM Card Installed” and renders the handset useless.

Notice how Apple suggests you restore your iPhone 4S to resolve the issue, ensuring that your handset receives the new software build 9A406 — the one Apple released a few days ago. The update obviously contained some sort of fix for the SIM card errors.

Have you been experiencing SIM card problems? Did this help?

  • Kok Hean

    Isn’t it unfair to those who are having issues on iOS 5.0.1? They have to download the firmware file and restore to that using iTunes.

  • Vitaliy T

    many people had that issue, glad Apple took care of it ^^

  • Anonymous

    I don’t have issues with mine since the start.

  • it was happening to me in iPhone 4 since iOS4

  • Jose Cheong

    umm this guide is stupid. You can easily just shift click upgrade and select the new 5.0.1 firmware and it will update to 9A406. I’ve done it on 2 of my 4s phones already no problem at all. Don’t be dumb and restore your phone.

  • Yes this new update solved the “Invalid SIM” issue which used to make your iPhone 4S useless as a phone! Some mobile carriers around the world were not identified in the previous build (9A405) for some reason. You can find a carrier having this problem in one country while the others carriers in the same do not have such problem. I am glad Apple solved the problem but in the same time I am surprised why Apple create such problem globally for iPhone 4S by mandating the identification of carriers!!

  • iPHONE 4S with 5.0.1 firmware (9A406) did not solve problem with SIM Card 64K or 128K ? Thank if you can help.

  • iPHONE 4S with 5.0.1 firmware (9A406) did not solve problem with SIM Card 64K or 128K ? Thank if you can help.

  • No New version is shit.I can not use my new iphone anymore .becz of Sim card is not valid errors come.
    want to go back verson but i cannot go.