crusader2015

Thanks @goodlogic. That did the trick. I have tested TATA CDMA SIM successfully, will check RIM in a while.

@vijaymalhotra_2007 - Can you please guide where can I find & change the "RUIM Preffer" in DFS? I can see RUIM CONFIG under Programming>General section which has 'RuimPref' as one of the values in drop down. Should I just select this & click 'Write' next to it? Thanks in advance.

Ok, so it looks like my driver installation was not properly done and the actual diagnostic port was not visible in DFS. I retried and can see all phone info in DFS with 'LGE AndroidNet USB Serial Port (COM10)' connected. A 6-digit SPC is calculated. I manually entered the SPC on top left and clicked 'Send SPC'. The log says DEVICE UNLOCKED. I also changed the Ruim Config to 'RuimOnly' in Programming>General>Config section and clicked 'Write' next to it. But when I restart the phone with Reliance CDMA SIM it still says INVALID SIM. Can someone please clarify the next steps in little more detail (step by step with screenshots)? I am not sure if I followed all required steps correctly.