Seeing “No SIM” or “Invalid SIM” on iPhone? Check your SIM card, restart, or update your carrier settings. Simple fixes often ...

A SIM card, or subscriber identity module card, is essential component of any phone. It connects your device to a cellular network and stores vital information, including your phone number. Many ...

Sareena was a senior editor for CNET covering the mobile beat, including device reviews. She is a seasoned multimedia journalist with more than a decade's worth of experience producing stories for ...

If you can't make a call or if you see an error message that your phone's SIM card is not working, there are several ways to troubleshoot the problem. Ther error ...