Unlock code for SGH-A197 Samsung?

As you have not specified in particular what is the unlock code required for you, i am giving the ways to unlock all the codes

NETWORK UNLOCK CODE:

You can unlock it by flashing your mobile if your mobile is a CDMA mobile...
The procedure for flashing your mobile is in the link below
http://hubpages.com/hub/How-to-Flash-your-cell-phone
It has an video explanation.

If your mobile is not an CDMA mobile , you can get the network unlock code(NUC) by just contacting the current network provider customer care department.It is free of cost.

The restriction code can be got from your old service provider..This restriction code is kept to prevent someone who stole the mobile from using it with another provider...

They will have a security check done with your date of birth etc..to verify whether you are the exact owner of the phone..

After that they will provide you the restriction code to unlock it and use it with another service provider..

Do not pay anyone for this seeing some advertisement over internet . That is all fake ads.

The above procedure works and you can verify that by seeing the rating of an happy customer here..
http://www.fixya.com/support/t4979448-need_unlock_motorola_razor_v3_from_optus

PUK CODE:

PUK code can be given only by your service provider which is specific for each and every mobile number.
Contact your sim customer care department over phone. Its free of cost to get the pin or puk no. If you cant contact through your phone get some other phone and contact them.
Go to the nearest service outlet of your service provider they can also help you.
There is no other go than the above procedure only your service provider can give it nobody else in this world nor any software...
Go to the below link and you can confirm that the above procedure works and there is a testimonial given by the customer too. http://www.fixya.com/support/t3079596-sking_puk_code

PIN CODE:

HI If you are asking for pin contact your service provider , he will give you a default pin .

If you try pin more than few predefined no of times your phone will ask PUK code which can also be given only by your service provider which is specific for each and every mobile number . Do not try PUK(new pin code) code many times or else your sim will be blocked and you will need a new sim.

Contact your sim customer care department over phone. Its free of cost to get the pin or puk no.
Go to the nearest service outlet of your service provider they can also help you.
There is no other go than the above procedure only your service provider can give it nobody else in this world nor any software..

SECURITY CODE:

If you are talking about the security lock code to enter into the phone then once it is lost nothing can be done except flashing the mobile . Because if anybody can give the security code created then who ever who steals your phone can get into it and get your valuable information.

So as safety precaution to avoid that they have designed it such that if you forget the security lock you have to reset the mobile memory by flashing the mobile at an authorized service center.So while flashing the mobile all the data in the mobile memory will be lost and you can again start using the mobile.

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