With helicopters there is a built in safety feature. The heli will basically not turn on unless all the settings are set so that the blades are not turning. It's to stop people not realising they have the heli on full power and connecting the battery which will then result in injury or at least a broken heli.

So when you connect the battery the throttle and trims have to be 100% all the way down and the reverse switches have to be the correct way or else all the way down could actually be full throttle.

If it is just the blades not turning it sounds like this is the problem. Please check the reverse switches are in the correct position and that the left stick is all the way down and the left trim all the way down. Also if you have an idle up switch make sure it is in the off position.

The motor will not calibrate for safety reasons until there is no signal at all telling the motor to turn so that the battery can be connected safely without the blades suddenly turning.

Once you have the controller set like this turn the controller on first and then connect the battery to the heli. The red light on the receiver should flash red a couple of times then go green.

If after this it does not calibrate you need to double check the following:

1. The battery for the helicopter is charged
2. The batteries in the radio controller are charged
3. The frequency plug is pushed securely into the receiver
4. The frequency plug is pushed securely into the controller
5. The number on the frequency plug in the receiver matches the number on the frequency plug in the controller.
6. Check the buttons are all on the correct settings as explained above. Make sure none are only half pushed. To be sure try turning them the opposite way and then back again.
7. Make sure the aerial on the radio controller is fully extended