How to master reset? without security code how to erase all contacts without security code?

check this one

Master Code Generator will Instantly generate your Nokia's Master security code.
This service can be used if you need to reset your Security Code.
Your IMEI: 356924034968264 --
Your Nokia Master Code: 2401254345


or this one


Nokia 5000 hard reset
You can format your Nokia 5000 device by typing: * + 3 + call + Power on. Before the device is reset, you need to provide the lock code. The default lock code is 12345.
If it is not working try this code:
You can format your device by typing *#7370# in standby mode. Before the device is reset, you need to provide the lock code. The default lock code is 12345.
Some Nokia phone can be reset via this menu option
Press menu button or enter Menu > Settings > Phone > Phone management > Factory settings > Delete data and restore > YESRestore factory settings
To restore the phone back to factory conditions, select Menu > Settings > Rest. factory sett. and from the following options:
Restore settings only - to reset all preference settings without deleting any personal data
Restore all - to reset all preference settings and delete all personal data, such as contacts, messages, media files and activation keys
IMPORTANT!
Formatting the device will permanently erase all user data and settings as well as add-on applications and operator specific settings
goodluck

Steps to perform Master Reset
All configuration settings will be set back to their factory defaults. Personal data and downloaded content, however, will not be lost.

1. From the standby screen, press Menu.
2. Scroll to and select Settings.
3. Scroll to and select Phone Settings.
4. Scroll to and select Reset Settings.
5. Select Master Reset.
6. Select Yes.
7. Enter Security code, then press OK. The default security code is 0000.

Steps to perform Master Clear
All configuration settings will be set back to their factory defaults. Also, all personal data (including contacts) and downloaded content will be erased.

1. From the standby screen, press Menu.
2. Scroll to and select Settings.
3. Scroll to and select Phone Settings.
   
4. Scroll to and select Reset Settings.
5. Scroll to and select Master Clear.
6. Select Phone.
7. Select Yes.
8. Enter Security code, then press OK. The default security code is 0000.

Warning!: While reset/restore operation under process, you are advised not to remove your battery until the operation is completed and cellphone restarts otherwise phone damage may occur.

Steps to Reset Phone Settings

This restores all the factory defaults, including the ringer types and display settings. The Recent Calls, Scheduler, and all text messages will be erased. Contacts are not affected.

1. Press Menu > Settings > Advanced > Reset Defaults > Reset Settings.
2. Enter six digit security code (default 000000) and press OK. (A disclaimer is displayed).
3. Read the prompt and press Yes to complete the reset.

Steps to Reset Phone

This resets phone settings and clears all phone data, including Contacts, History, Scheduler, and Messaging.

1. Select Menu > Settings > Advanced > Reset Defaults > Reset All.
2. Enter six digit security code (default 000000) and press OK. (A disclaimer is displayed).
3. Read the prompt and press Yes to complete the reset.

Warning!: While reset/restore operation under process, you are advised not to remove your battery until the operation is completed and cellphone restarts otherwise phone damage may occur.*Disclaimer:Performing a master clear/master reset/hard reset will erase all your data (photos,videos,contacts etc) completely and reset all the settings to Factory default. The information contained in this website is for general information purposes only.In no event will resetcellphone.com be liable for any loss or damage including without limitation, indirect or consequential loss or damage. For complete disclaimer notice please visit Disclaimer. The brand names are the registered trademark of respective manufacturers.

There is not master reset code, if there were your PIN would be worthless as a security feature, you must do a hard reset of the phone to erase the PIN. Contact your phones service provider for help with this.

NOTE: Performing a Master Reset on any Cell phone will Master reset your cell phone and erase the phone completely including contacts, pictures, videos etc.


To perform a master reset on your Nokia 6300 or 6301 you will need to:
on your Nokia 6300, 6301 dial *#7780# eneter your security code (default is 12345)
NOTE: Performing a Master/Hard Reset on any Cell phone will Factory reset/clear your phone and erase the phone completely including contacts, pictures, videos etc.

try master reset codes from http://www.unlock-free.com/ to reset your phone and erase the security block

Unfortunately a master reset is in order, go to master clear. It will ask for a security code. It should be six zeroes (000000). This will erase everything on the phone- contacts, texts, etc.

Master Reset
Reset all options except unlock code, security code, and lifetime timer:

Go into Settings > Initial Setup > Master Reset

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Master Clear
Caution: Master clear erases all information you have entered (including phonebook and datebook entries) and content you have downloaded (including photos and sounds) stored in your phone’s memory. After you erase the information, you can’t recover it. Clear all settings and entries you made except SIM card information, erase downloaded pictures and sound files, and
reset all options except unlock code, security code, and lifetime timer:

Go into Settings > Initial Setup > Master Clear

Here is how to do it on the Samsung M220, maybe it will work for your Samsung phone too:

Menu > Settings> More > Security and enter your lock code (last 4 digits of your phone number)
Select Erase/Reset
Select an option - in this case choose Erase Contacts

You can always contact Nokia. They will tell you the master reset code, but it will erase all of your current info.