I'm from America but I'm studying in London. I have my sim from back home with me and I have a phone contract here as well. I bought myself a cheap Belkin wireless G router. I installed it and my computer works fine on it. When I use my local sim and try to go on Wifi, it finds and connects to my network just fine. However, when I put in my t-mobile sim from back home, it DOES NOT find the network SSID in the list of available wifi networks. BUT, when I take my phone to school, put in the t-mobile sim, and connect to my school's wifi, it connects just fine and I am able to make phone calls to USA. I don't know why it's doing this. Summary: Out in London Local sim connects to wifi just fine. USA sim connects to wifi when I try from school, but it doesn't even find the SSID on my home router. What is going on?