Central Locking?

Can anyone please give straight answers.
I have been trying for months to solve the problem
on my Astra 16.00cc G 2003. It has only two locks.
The Drivers and the Boot. I have tried putting the key in the Ignition turning it to the second possition, pressing the un-lock button.
I tried doing it with the lock button.
I tried one after the other.
I tried on the first possition, as above.
I have reset the key to the car on the second possition holding the button till the red light stops flashing. Still the central locking doesn't work.
I have checked the DTC and it say's all is working and signal is being received. Can anyone please give me the secret to getting it working? Barrel is fine.