Fix “No SIM Card Installed” Error on iPhone 4S by Installing iOS 5.0.1 Build 9A406

iPhone 4S is specially built to support the iOS5.0.1.This operating system is enabled to fix the SIM card issues in iphone previous version. This error was making users angry as the operating system was not capable enough to connect to the network supplier server. The error messages usually shown on the screen is as “No SIM Card Installed” or “Invalid SIM”. In the latest versions the user can manually fix this error and the procedure is as stated below.

To resolve the error, users have two choices:

  • The first option recommended by the Apple Company is to set backup on itunes and then restore from the last backup. This is very easy way and highly practiced for resolving this error.
  • The second way of fixing this problem is to download a file with the title 9A406 directly from the internet and reinstall the software manually using IPSW. This option is for advanced users who have proper information and experience of how to perform these steps.

The latest iOS 5.0.1 updated version is providing solution to all the users of iPhone 4S who frequently face such kind of errors.