Samsung SCH-W550 hard reset code
then search cdma keran codes and found the solution:
ZAKIR GSM
1.- Press menu
2.- Press SOS
3.- Select User Input
4.- Digit 5809540*45680 then the pone input in TEST MODE
5.- Digit 088
6.- Select 1 the phone show: EFS clear and change to white scren
7.- Wait be patient to show Done and the phone restart