You received this message because you tried to use a device that isn’t supported on our network. The most common reasons a device won’t work are:
Devices that don’t use the same cellular technology and frequency bands as AT&T aren’t able to use our network services.
If you want to bring your own device, learn about devices that work on our network (PDF, 552KB).
Or, you can shop our best deals on AT&T Wireless or AT&T Prepaid devices.