I guess your phone locked to particular Network.That's why it's shows enter code.You can get the unlock code for your Sony Ericsson C902 phone from http://www.classicunlocking.com/sony-ericsson-c902/rs16wp9/ by submitting,country,Network name,IMEI number of your phone.Then they deliver unlock code to you through mail with unlocking instructions.Using this you can unlock your phone easily.
sahana
September 2013
sonyericssan c902 code
kamran
April 2010
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