i have been trying to discover if we can unlock the american lte frequencies through software only & ran across a thread online which allows u to enable/disable individual bands...i will see if i can hunt down the original post as i wouldnt want to claim the fame if it works for u but try this
!. dial *#0011# which will take u to service mode
2. press the 3-dot menu button then hit back (NOT the hard button)...do this again & u will end up at the main menu
3. choose selection  ue setting & information, then  setting, followed by  protocol , next  nas, after that  network control
4. finally pick  band selection & this will bring u to the page where u want to be...just remember that an asterick means its selected
always use "3 dot menu-back" & NOT the physical buttton...dont forget to press the '"apply band configuration" when you're done & then "menu-end"
Thank for this very useful information, WIND uses AWS, with bands 1700/2100, I selected those frequency when I was in the menu and made sure to press apply band configuration, i restarted the device, but still not registering on WIND network. however now for the first time I see the network signal strength full. Did I miss anything?