try these code out..

Samsung 600:
*2767*3855# -> Full EEPROM Reset (Remove SP-Lock)
*2767*2878# -> Custom EEPROM Reset

others:
Samsung Reset Codes
You can try these in case you downloaded corrupted or incompatible Java midlets or other media, which are causing problems with the phone.

1. *2767*JAVA# Java Reset and (Deletes all Java Midlets)
2. *2767*MEDIA# Reset Media (Deletes All Sounds and Pics)
3. *2767*WAP# Wap Reset
4. *2767*CUST# Reset Custom EEPR0M
5. *2767*FULL# Reset Full EEPR0M (Caution)
6. For example : *2767*JAVA# would be keyed in as *2767*5282#

Other Samsung Codes
1. *#06# IMEI code
2. *#9998*4357# Help Menu
3. *#9998*5282# Java menu (GRPS/CSD settings for JAVA server)
4. *#9999#0# Monitor Mode
5. *#9999# or *#9998*9999# Software Version
6. *#8888# or *#9998*8888# Hardware Version
7. *#9998*746# or *#9998*0746# or *#0746# Sim Infos
8. *#9998*523# or *#9998*0523# or *#0523# Display Contrast
9. *#9998*842# or *#9998*0842# or *#0842# Vibration On (until you push OK)
10.*#9998*289# or *#9998*0289# or *#0289# Buzzer On (until you push OK)
11.*#9998*288# or *#9998*0288# or *#0288# Battery & Field Infos
12.*#9998*377# or *#9998*0377# Error log
13.*#9998*778# or *#9998*0778# or *#0778# Sim Service table
14.*#9998*782# show date and alarm clock
15.*#8999*638# show network information
16.*#9998*5646# change operator logo at startup
17.*#9998*76# production number
18.*#9998*968# view melody for alarm
19.*#9998*585# Non-Volatile Memory (NVM)
20.*#3243948# Digital Audio Interference Off
21.*#32436837# Digital Audio Interference On

Hope it helps.

Good Luck.