Previously activated iPhone 3GS I've just upgraded to an iPhone 4S, and I want to use my old 3GS like an iPod touch. I have updated the software using iTunes and now on iTunes it says:

There is no SIM card installed in the iPhone you are attempting to activate.


How do I get around this?
Is there a SIM card in it?

If not, go to a store and pick one up for a couple of pounds/dollars/rupees/whatever, pop it in, activate it, and hey presto you have an iPod touch. You need to keep the SIM card in otherwise it will not function.