Phone lock code of k550i

You can Unlock the mobile phones from the Security Lock(Password) lock using the Master Reset Code,You can get the Master Reset Code at Reliable Cost here
http://www.mobileunlocksolutions.com/unlocking-services/rs1wp6/ and Unlock the mobile from the Security lock,You Can Check whether Your model in the List!!!!!!!!!

To Unlock the Sony Ericsson K550i Mobile from the Network Lock You can use the Unlock Code,You can get the Unlock Code at
http://www.wickedunlock.com/sony-ericsson-k550i/rs11wp9/ and Unlock from the Security lock use the Master Reset Code.

As a default Sony Ericsson does not provide such facility to lock your Phone keypad with password.
For any clarification regarding this please revert back.
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To protect your phone from unauthorized use, just follow these simple steps. Once activated, your phone will require the user to enter a password each time it?s turned on. Go to Menu > Settings > General > Locks > SIM Lock > Protection. To turn your PIN code request on, you will be prompted to enter a 4 to 8 digit phone code (that you create) Call Cincinnati Bell Customer Care at 611 to obtain a PIN/PUK code to enter at the prompt. here is the link k550i Happy new year and Happy Sunday

The default lock code for Sony Ericson is "0000"

Someone told you the motherboard is out of service? Does this mean it is broken?
did the provider put a lock in it from non payment?
If they did you may be able to reflash that software and clear the lock.
or get an unlock code to clear the provider locks.
If the mother board is just damaged, then replace it, but if its not damaged the phone can be unlocked from your provider

hi i have a sony ericsson k550i phone and i put a lock code on it but i don't remember the code 

it is the last four digts of your phone number.

plese rate

sonyericsson.com

What kind of code is it asking for?

If it ask for a PIN code then it means it's asking for the password/code you have entered on your SIM card. If it asks for Security code then that means it's the password/code for the phone.

Entering three invalid PIN codes on your phone then your PIN may be locked and you can only unlcok it by entering the PUK code on your SIM. PUK code is available on the sim card pack. Once it's ented, you have the option of changing your PIN code. Just be sure to remember your PIN code so the same incident won't happen again. If it ask for security code, enter the code you have for the phone but if you don't remember setting a security code, then you may try the default security code of Sony Ericsson phones which is 00000.