Iphone 4s not Recognising SIM card after iOS 7 upgrade

[Kapang]

I've just upgraded my 4s to the iOS 7 but now it says that it no SIM card is installed.
I've rebooted several time the phone and even removed/inserted the SIM card but nothing happens.
Can anyone help with this one?

Thank you.

 

[Just_Me_D]

Some people have found that turning on Airplane mode and then turning it off rectifies the problem. Give it a try. It may work for you. Anyway, Merry Christmas to you and your family...