there No Solution to Unlock K750 CID49.
Even Semc 8.4 Cracked Can't Do it Successfully.
Better goto any GSM Service Center and pay Some bucks instead of Dead Phone
BR.
Yes i did that after i bricked my K750i CID 49 T-Mobile branded
now the flash it sucsesful wit a custom sony firmware.
did cost me 20 euro's.