Your SIM card or device may be configured for your previous network and will need to be reconfigured. Clean the gold connectors on the SIM with a clean lint-free cloth. Replace the battery and turn your phone on without the SIM. Turn your phone off, replace the SIM and restart the phone.
Regarding this, how do I activate a new SIM card in my iPhone?
Before you can use your iPhone, you'll need to insert your SIM. To activate the iPhone, you'll need to connect to our 3G network or Wi-Fi. If you don't have a 3G network or Wi-Fi connection, click here to complete your iPhone activation using iTunes.
How do you activate a SIM card for Verizon?
Switch on the cell phone by pressing the power button. 6. If your phone is ready then dial “(877) 807-4646” from the dial pad. If you are a Business customer then you should call “(800) 922-0204” to activate your SIM.
How do you activate a Vodafone SIM card?
Turn your phone on and dial 1300-101-606 from the phone's keypad. Wait until you are connected to a Vodafone representative and explain that you want to activate your SIM card. If it is an automated message, wait for the voice prompts and choose "Activate" from the automated menu.