The options I have are GLOBAL, LTE/CDMA and LTE/GSM/UMTS. If I selected either of the first 2 the Network Operator is greyed out. But when I select LTE/GSM/UMTS it allows me to select Network Operators, then I can choose Search Network or Select Automatically. If I choose Select Automatically it tries to search and after 1 minute or so it says Unable to Connect. When I choose Search Network and then hit Manual after 30 secs or so it gives me the choices of AT&T, T-Mobile and Verizon Wireless. I hit T-Mobile and after about 30 secs of trying to Register a small menu pops up asking if I want to switch to GLOBAL for the Network Mode. If I hit Cancel it continues to search and after about 30 secs the menu pops up again. If I choose OK then it switches to GLOBAL and then says Unable to Connect.