What is a CARRIER LOCK?
From EjWiki
SIM lock: A SIMLOCK, NETWORK-LOCK, CARRIER LOCK, imei lock or (Master) SUBSIDY lock is a technical constraint built into GSM and CDMA smartphones by manufacturers for use by carriers to restrict using these phones to a particular locations and/or networks. This is unlike a cell phone (retrospectively called SIM-free or unlocked) which doesn't enforce any SIM restrictions.Unlocking a smartphone is practically universally legal. Additionally, it's legal for providers to force SIM locks for certain amounts of time, differing by location.
Unlocking Technology: A mobile phone can be unlocked simply by entering a code provided by the network operator. Alternative mechanisms incorporate software running on the handset or a pc attached to the device, hardware devices that link to the phone or over-the-air by the service provider. More often than not the unlock process is permanent. The code needed to eliminate all locks from a cellphone is called the master code, network code key, or multi-lock code. Generally if the device is carrier locked it will typically display one of these messages: SIM network PIN blocked, Enter lock PIN.
Economics: Quite often a SIM-locked device is available at a noticeably lower cost than an unlocked one due to the fact the company plans income via its service. SIM locks are applied on cheaper (pay-as-you-go) devices, whilst bargains on more costly handsets require a subscription that delivers guaranteed income. Unlocked mobiles have a much higher market value.
Unlocking Services: A certain amount of companies provide a phone unlocking service. This service requires people whom want to unlock a device to supply their IMEI number to a unlocking company and quite often they will also ask for the country and cellular network the mobile phone handset is locked to, either sent by email or submitted on their website. The supplier then will supply (for a fee) the unlock code for the device.
Unlocking Service Providers: Unfortunately there are a lot of dodgy sites active in the cell phone network unlocking industry. Consequently it is advisable to make sure you find a genuine provider for this service. Take the necessary precautions and investigate all potential dealers in advance of choosing to submitting an order. In the case of on-line sellers, make certain they specify their official business name and corresponding registration details (all authentic enterprise has to be legally registered with the official authorities within their country of origin) and ensure they supply a genuine registered address and contact information on their web-site. Additionally ensure that any payments made are done so by legitimate methods such as a recognized bank or financial institution using a debt or credit card, but never ever make payment via a direct transfer since this offers no fiancial safeguards. To assist with a search for a legitimate service provider, we've provided a checklist beneath (and in no particular order) of several legit organisations currently offering such services.
Reputable Mobile Phone IMEI Unlocking Service Providers: DoctorSIMUnlock.ZoneUnlock BaseUnlock RiverCell UnlockerMobile Unlocked
