How to unlock iphone 3gs

Iphone Unlock Code

I need to unlock my iphone to use it on t-mobile.

Hi, the best option is to use a carrier authorized unlock, check here if your current network is supported for unlocking: 
http://www.fastgsm.com/en/apple/apple/apple-iphone-3gs/unlock/country-network

If you need to unlock Apple Iphone 3gs,Use Remote unlock service.You can get remote unlock service fromwww.mobileunlocksolutions.com
To get remote unlock service, you have to provide the country and network in which it is currently locked,IMEI number.Then get unlock and unlock it.

The default phones code is 12345 or 00000 u can use it 

Default 4 Digit user code: 1234 or 0000

Default 6 Digit Security code: 123456 or 000000

Type *#06# at the mobile screen to know IMEI no of your mobile.

send the IMEI no to the service provider and they will reply you with unlocking code.

IF Problem not Solved 

You need to install  New Software in the Phone.

If For puk & pin cod problem 

You Go To Service & Sim Office and Get The Puk code And Pin code From Office oprator

Enter The Puk code and Yes

Enter The pin code and Yes

The correct Puk code will Open the locked cell phone and Problem will Quickly Solved.