The Nokia 1661-2B is a GSM-based cellphone. GSM cellphones rely on SIM card technology to connect to specific wireless network carriers. When a phone is “locked” it means that the phone can only be used with one particular network carrier, such as T-Mobile. Unlocking a Nokia 1661-2B allows you to use the phone with any GSM network carrier. Unlocking the phone involves obtaining the unique SIM unlock code for the Nokia 1661-2B you own, and inputting the code into the phone. Tips Writer Bio
