Samsung SGH-A157

SGH-A157:

Step 1: Remove sim card from phone and turn the phone on.

Step 2: Dial *2767*3855# This will  initiate a Full reset for Samsung A157

Step 3: Once the phone restarts, dial #*7337# This will remove sim lock and reset phone

Step 4: Now insert your sim card. and restart the phone.

DONE.