What should I do when iPhone5 says no sim card installed, I'm unable to use phone?

[iMore Question]

What should I do when Iphone5 says no sim card installed, I'm unable to use phone?

What can I do when IPhone 5 says no sim card? I am unable to use any functions.

 

[SwitchBeach]

Re: What should I do when Iphone5 says no sim card installed, I'm unable to use phone?

Do you have a SIM card installed?
Have you tried popping it out and putting it back in?
Is the SIM card from a carrier that is compatible with the phone?