SM-A300FU Version 5.0.2 Unlock Done!
no need to root just click Direct unlock
UNLOCK INSTRUCTIONS:
Micro-USB cable:
1. Phone must be powered on.
2. Type *#0808# and select 'DM+MODEM+ADB'.
3. Type *#9090# and choose 'DM/DUN over HSIC' (ignore it, if it's not available).
4. Reboot phone.
Or use 'Activate Diag' function from 'Repair' tab.
5. Connect USB cable, install drivers if needed.
6. Select Samsung diagnostic port in port settings.
7. Press 'Unlock' button for direct unlock.


no need to root just click Direct unlock
UNLOCK INSTRUCTIONS:
Micro-USB cable:
1. Phone must be powered on.
2. Type *#0808# and select 'DM+MODEM+ADB'.
3. Type *#9090# and choose 'DM/DUN over HSIC' (ignore it, if it's not available).
4. Reboot phone.
Or use 'Activate Diag' function from 'Repair' tab.
5. Connect USB cable, install drivers if needed.
6. Select Samsung diagnostic port in port settings.
7. Press 'Unlock' button for direct unlock.

