No SIM Card installed error in iPhone 3g My device iPhone 3G shown " "No SIM Card installed" 'insert a valid SIM With no PIN lock to activate iPhone' " It is in Emergency mode so please give me a solution if there is..? It comes when i am tried to Updating the ios From 4.1 to 4.2.
i am in india and i got it from USA. i didnt have any USA sim.. so please tell me what i do?

Thank you.
Consider the possibility for your SIM card to have failed. It happened to me and I had to go to a phone store and get a duplication of it. Here in Europe it costed me 6€ to have a duplicated SIM. It took about an "hour" to be activated, but after that, it started working. 

Try using your SIM card on another phone if you have one around or go to an Apple Store and see if you can test the SIM there.