I have an iPhone 4s Verizon phone, still active, "unlocked" for foreign SIM use, and tried to insert a LIME Caribbean CDMA Jamaican SIM card in it to use it while I am here on vacation. I did that last year and it worked fine.
But when the new SIM was inserted, the phone said it was trying to activate, and went looking for a WIFI connection to do that. The LIME people weren't able to figure out what to do...no surprise...tiny little store with no tech support...suspect they don't deal with US iPhones often, or ever. But it worked last year.
Oh, and when reinserting the Verizon card, it also required registration or activation...same screen. And I haven't been able to get my roaming Verizon service (in Jamaica) working yet either. I remembered something last year that involved iTunes, so I went there and tried to find a connection, but my iPhone still says "No Service" rather than "roaming", which it did before I tried the other SIM card in it.
I definitely want to ensure you get the connection you need! The iPhone 4S is unlocked for global usage, so using a local SIM card is definitely an option. You would need to work with your local carrier direction for assistance connecting using their SIM.
For the VZW SIM, we can definitely assist! Do you currently have a VZW account? Have you been able to activate your SIM and device online? http://vz.to/1dy7Mcv
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