I downloaded ios 8, now I can't message my family. I get "not delivered" (!)

Hi voracious,

Thanks for visiting Apple Support Communities.

It sounds like your sms or iMessages are not sending after updating to iOS 8. You can use these steps to troubleshoot this issue and get those messages sending again:

1. Go to Settings > Messages > Send & Receive and make sure that you registered iMessage with your phone number or Apple ID and that you selected iMessage for use. If the phone number or Apple ID isn't available for use, troubleshoot iMessage registration.
   
2. Open Safari and navigate to www.apple.com to verify data connectivity. If a data connection isn't available, troubleshoot cellular data or a Wi-Fi connection.
   
3. iMessage over cellular data might not be available while you're on a call. Only 3G and faster GSM networks support simultaneous data and voice calls. Learn which network your phone supports. If your network doesn't support simultaneous data and voice calls, go to Settings > Wi-Fi and turn Wi-Fi on to use iMessage while you're on a call.
   
4. Restart your device.
   
5. Tap Settings > General > Reset > Reset Network Settings on your iPhone.

If this is only happening when sending text messages to family (and you can message others,) try these steps as well:

1. If the issue occurs with a specific contact or contacts, back up or forward important messages and delete your current messaging threads with the contact. Create a new message to the contact and try again.
   
2. If the issue occurs with a specific contact or contacts, delete and recreate the contact in the Contacts app. Create a new message to the newly created contact and try again.

You can find this information and even more troubleshooting steps at this link:

iOS: Troubleshooting Messages

All the best,

Jeremy