Unlock Service Provider Lock

Here is a way to Unlock your phone which is Service Provider locked, without to know SPLock code. With a Nokia 16xx/21xx/31xx/51xx/81xx that are SIMlocked to one privider you can bypass the SP lock like this-

First of all, PIN CODE MUST BE ON, then press-

C

C and hold until it clears display
* and hold until start to blink
* and hold until start to blink
04***your pin>#

Each time you turn your phone OFF it resets the lock, so this need to be done each time you ll turn your phone ON

The phone now says- PIN CODE CHANGED (or ACCEPTED)
and the SIM card is accepted until you restart the phone again.

NOTE- On vesion 5.04 Nokia has removed this option.

update-
There s another Nokia service provider lock generator for DOS (somewhere on the net) called 5161un.zip (for Nokia 51xx-61xx models) This program uses the #pw+(master code)+1# code to unlock the phone. With this software you need to have a access to the eeprom.