Some unlock codes for Samsung phones, these are entered on the keypad although i am not sure for all models whether the SIM should be removed or not, i'm afraid it's upto you to try, these codes generally reset part of the phones EEPROM so these are strictly use at your own risk i'm afraid.
*#7465626# should show you the lock status, but i am not sure if it works on all phones.
E700 / S500 :
*2767*688#
SGH-600 :
*2767*3855# - Full EEPROM Reset
*2767*2878# - Custom EEPROM Reset
S100 / S300 / V200 :
*2767*7822573738# - Stack Reset
S105 :
Remove SIM
Enter *2767*7822573738#
After reboot enter #0111*00000000#
Message should show saying "Personalisation Cancelled"
A300 / A800 :
*2767*637#
A few more.
You can try these in case you downloaded corrupted or incompatible Java midlets or other media, which are causing problems with the phone.
*2767*JAVA# Java Reset and (Deletes all Java Midlets)
*2767*MEDIA# Reset Media (Deletes All Sounds and Pics)
*2767*WAP# Wap Reset
*2767*CUST# Reset Custom EEPR0M
*2767*FULL# Reset Full EEPR0M (Caution)
For example : *2767*JAVA# would be keyed in as *2767*5282#
Note : Not all codes will work with SGH-C100.
Other Samsung Codes
*#06# IMEI code
*#9998*4357# Help Menu
*#9998*5282# Java menu (GRPS/CSD settings for JAVA server)
*#9999#0# Monitor Mode
*#9999# or *#9998*9999# Software Version
*#8888# or *#9998*8888# Hardware Version
*#9998*746# or *#9998*0746# or *#0746# Sim Infos
*#9998*523# or *#9998*0523# or *#0523# Display Contrast
*#9998*842# or *#9998*0842# or *#0842# Vibration On (until you push OK)
*#9998*289# or *#9998*0289# or *#0289# Buzzer On (until you push OK)
*#9998*288# or *#9998*0288# or *#0288# Battery & Field Infos
*#9998*377# or *#9998*0377# Error log
*#9998*778# or *#9998*0778# or *#0778# Sim Service table
*#9998*782# show date and alarm clock
*#8999*638# show network information
*#9998*5646# change operator logo at startup
*#9998*76# production number
*#9998*968# view melody for alarm
*#9998*585# Non-Volatile Memory (NVM)
*#3243948# Digital Audio Interference Off
*#32436837# Digital Audio Interference On
These are done at your own risk.
*#06# -> Show IMEI
*#9999# -> Show Software Version
*#0837# -> Show Software Version (instructions)
*#0001# -> Show Serial Parameters
*#9125# -> Activates the smiley when charging.
*#8999*228# -> Battery status (capacity, voltage, temperature)
*#8999*246# -> Program status
*#8999*289# -> Change Alarm Buzzer Frequency
*#8999*324# -> Debug screens
*#8999*364# -> Watchdog
*#8999*427# -> Trace Watchdog
*#8999*523# -> Change LCD contrast - Only with version G60RL01W
*#8999*544# -> Jig detect
*#8999*636# -> Memory status
*#8999*746# -> SIM File Size
*#8999*778# -> SIM Service Table
*#8999*837# -> Software Version
*#8999*842# -> Test Vibrator - Flash the screenligth during 10 seconds and vibration activated.
*#8999*862# -> Vocoder Reg - Normal, Earphone or carkit can be selected
*#8999*872# -> Diag
*#8999*999# -> Last/Chk
*#8999*9266# -> Yann debug screen (=Debug Screens?)
*#8999*9999# -> Software version
*0001*s*f*t# -> Changes serial parameters (s=speed, f=0,1, t=0,1)
*2767*927# -> WAP Reset (re-enable WAP on phone) **
e700, e710, x100, x600 unlock #*7337#
this one is for the e720 and works a treat
Samsung Remote Unlock Instructions:-
1. Switch OFF your phone.
2. Put in a SIM of a different network provider.
3. Now turn your phone back on. You will see an error message saying
"Wrong Card".
4. Type *#9998*3323# in to your phone.
5. If you've entered the code correctly as outlined in the Step 4, you
shall see a screen telling you to press exit. So hit the right soft key.
6. Now you will see a Menu of choices. Scroll down and select option 7
(“Jump to Null”). As soon as you select option 7, your phone will turn
black and reboot itself. After your phone reboots, the SIM will be
recognized and your SIM will work. (Please be patient while your phone
reboots and DO NOT press any keys.)
7. Now, at your welcome screen type in *0141# and hit your call button!
This will give you a message saying your phone is Personalized.
8. Power OFF your phone and insert your original SIM.
9. Once done, power ON your phone.
10. At the SIM Code prompt, it will ask you to enter a password. Type
00000000, (that is 8 Zero's). After you enter the code, hit "ok" and
your phone should power up.
Your phone is unlocked!!!
You can now put the SIM of your choice into the phone and use it at your
will! Without ANY RESTRICTION!!!