Those of you who own an iPhone 4S might have come across this error, the “No SIM Card Installed” or “Invalid SIM”. Fear not folks there is a solution on how to resolve this SIM error on the iPhone 4S.
As you might be already aware that Apple silently launched a new firmware, no not iOS 5.1 but iOS 5.0.1, the one that got re-released. Many wondered why Apple released a new firmware with the same name as previous one. It seems that mostly iPhone 4S users were affected by this no SIM card problem so they did not need to launch a whole new one.
If you are one of those users who have been affected by this problem simply download the latest firmware from Apple.
Fix No SIM Card Problem
To fix the invalid SIM problem simply follow the steps below.
STEP 1: Back up (Using iTunes)
- Connect your iOS device to a computer with the latest version of iTunes installed
- Select your iOS device in iTunes under Devices
- Right-click (or Control-click) the device and select Back Up
STEP 2: Restore your iPhone 4S from iTunes
STEP 3: Restore your content and settings from back up
- Right-click (or Control-click) the device and choose Restore from Backup
The invalid SIM problem should now be fixed. If you still see the same problem let us know in the comments below and we will try to help you out.
This re-released iOS 5.0.1 also solves the battery problem, so if you are still facing the problem you should update too.