Iphone 4s- Invalid Sim

Hey guys,

I'm a newbie to the iOS fanbase. After lot of struggle, i got an Iphone 4s. This is my first iOS device. The biggest mistake I made was getting it from the UK.

I asked my uncle, to get it from there. The one he bought was a factory unlocked one. The mistake he made was, he had forgotten to activate it using a UK based micro sim.

I dint noe tat, this needed to be done. After spending a week, trying out different carrier Indian microsim, a friend of mine who is in the Tech field, told me that this was manufactured in the first batch and that it had to be activated using the country sim from where it had been bought.

Note: I couldnt even use it as an Ipod Touch.

Again, after enquiring a lot of people, I managed to get an Orange microsim in Chennai itself. It successfuly got activated and since it was on International roaming, it showed full signal on Vodafone carrier. just when I thought everything was going fine, I took the Orange sim out and inserted a cut Airtel microsim and the deadly "Invalid Sim" error came up. The same came up with a Cut Vodafone microsim too. BTW my phone is running on 5.0.1. So now, I can use my Iphone only as a very expensive touch with Siri. Need Help Urgently.

Cheers