It has been reported that iPhone 4S may not recognize a micro-SIM card. This may result in receiving an error message stating “No SIM Card installed” or “Invalid SIM”. This bug has been fixed by the latest iOS version. If you encounter this problem, you should update to iOS 5.1 or later.
Obsessed with tech since the early arrival of A/UX on Apple, Sudz (SK) is responsible for the editorial direction of AppleToolBox. He is based out of Los Angeles, CA.
Sudz specializes in covering all things macOS, having reviewed dozens of OS X and macOS developments over the years.
In a former life, Sudz worked helping Fortune 100 companies with their technology and business transformation aspirations.