Flash/Flex
These terms refer to what needs to be done to an unlocked or unbranded phone to work properly on your carrier. If you have an unlocked phone, and you pop in carrier A's sim card, the voice aspect will work ok. Now if you need mMode, Tzones, or Cingular's internet, the phone will have to be flashed and flexed to allow the text, internet and SMS messages to work. Most of this can be manually programed. Call you carriers tech support to help with the settings.
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