@justme is it :) I unlock my k610i CID 52 db2020 in Mobile service for 100zł(PL) = 26 euro, i get 2 NCK code (unlock,lock) for my IMEI and Operator Network and i must just enter code to menu service <**< Network -> NCK code and i have now unlock mobile phone :) My friend wont unlock he phone and i searching this NCK code calculator in Internet :) sory for my English I'm from Poland.