Liberating Your Locked GSM Phone

Wireless carriers sell you "postpaid" contract phones at a considerable discount. The carrier expects to recoup its outlay -- the full price of the equipment -- over the life of the contract that you sign. Often, it will lock the equipment to its network through a technique that stops the phone working if the SIM card ID and the phone serial number, aka "IMEI number," don't match what's configured.

Source: http://ectnews.com.feedsportal.com/c/34520/f/632000/s/205831d4/l/0L0Stechnewsworld0N0Crsstory0C753710Bhtml/story01.htm

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