As I did not have the code yet I hit ignore so I could install CM9.
Now I have the code I put in the giffgaff sim but no code prompt appears and the phone just boots up with no service.
I have also tried other networks' sims but it's still the same.
There was a thread with the same problem on the giffgaff forums which was solved by rebooting with no sim then with the giffgaff sim
I have tried this but no luck
My giffgaff sim is fully activated and working.
Is there a way of forcing the sim unlock code entry screen to appear?