In order to use Korean simcard in Korea, device should be unlocked. You
can check it through your current mobile carrier in your country before you
come to Korea.
Whereas a locked cell phone will only accept SIM cards from its current
provider, an unlocked cell phone will accept a SIM card from any service
provider. (This is very useful if you want to use your phone abroad, for
example.) To identify an unlocked cell phone, follow these steps.
Turn off your cell phone, remove the battery cover and battery, then look
for the SIM card.
1) If you cannot find a SIM card in
the back, look for one in the side or top of the phone. It may be covered by a
small plastic flap. On some models, you will need to open the flap with a pin.
2) If your cell phone operates without a SIM card, it is a CDMA
(Code-Division Multiple Access) phone, as opposed to the more common GSM
(Global System for Mobile communication). CDMAs cannot be unlocked.
different service provider's SIM card into your phone and close it back up. For
example, if you have T Mobile, insert a Cingular
SIM card. The easiest way to do this is to borrow a phone from a friend.
Turn on your phone.
Try to access the phone book or make a call. If the phone functions
normally, you have an unlocked cell phone. If it says “Restricted,” “Contact
Service Provider,” etc. (in other words , doesn’t allow you to access your
phone book or make calls), you have a locked phone that won’t accept other SIM
cards from other providers.
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