I'm not a real cell phone tech but when I got home I turned on the cell phone and it just started seaching for a network with no luck. Since the phone was tri-band I remembered that the European GSM uses the frequencies of 900 and 1800 MHz and the North Americans (AT&T) use the 800 MHZ frequency. They may also use the newer frequency of 1900 (or maybe 1950, I'm not sure). So, you have to set the phone to look in the correct frequency area. Anyway I went into the Main Menu on my cell phone, found Settings and Network and selected the 800 MHz frequency. I turned the phone off and on and it again searched and this time it found AT&T. It even said AT&T/Tesco on the cell phone screen. I made a call and it worked. AT&T even displayed my Tesco balance when the call was ended.

Another thing we found out which might be a problem is when we were on the island of Majorca using an Italian TIM SIM card and we wanted to dial a local Majorca phone number, we had to dial the entire phone number, the European access code "00", the country code "34" and the phone number "616 555 000" which was "0034 616 555 000".

Now, for you Linda, I removed the Tesco (UK) SIM card from my cell phone (remember, I had already charged the network frequency) and inserted the Italian TIM SIM card and turned the cell phone back on. I'm located 13 miles from Chicago. The phone searched for a network and found two, AT&T and Voicestream. I selected AT&T and then the phone Registered.

I attempted to call my home phone number but I got an error message in English. Then I tried to call using the European access codes "001... and my phone number with area code. I got an Italian speaking voice informing me that I had no credit on this SIM card, which I already knew. In summary, make sure you are on the right network frequency.

I have credit on the Tesco SIM card that originally worked.

SIM cards do expire and credit balances will also expire if not used for a few months. This depends on the company.

One additional item, if you intend to use one SIM card throughout Europe you have to top up or recharge your phone before you leave the country where you bought the SIM card. And you must be prepared to pay a little more for your calls outside your "SIM card country". Since the price of a SIM card in Italy and the UK was under $10US it might make more sense to buy a new SIM card in each country. Also remember, you can text message someone at home your new number very cheaply and they can call you back. Incoming calls in Europe are free.

I also put the French SFR SIM card in the phone and it worked with AT&T but I received several text messages from SFR informing me that I had no balance but I could call a number and recharge my phone with a bank card.

I assume that both the French SFR and the Italian TIM SIM cards would have worked if they had any credit left because I received the text messages and the SFR text messages always started out with "Bienvenue aux Etats-Unis".

Both the Italian and French SIM cards have zero (or close to zero) balances.

Let me know if this helps, John Vittoe