What is a SIMLock

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SIM lock:

A simlock, NETWORK LOCK, carrier-lock, imei-lock or (master) SUBSIDY lock is actually a technical constraint built into CDMA and GSM cellular phones by producers for use by providers to limit the usage of these phones to a particular locations and/or networks. This is in contrast to a phone (retrospectively called SIM-free or unlocked) which doesn't enforce any SIM constraints.Generally if the phones were not locked, consumers can sign an agreement with one supplier, get the marked down phone, then stop paying the monthly bill (thus breaking the agreement) and start using the cell phone on another mobile phone network or even sell the device for a profit. SIM locking curbs this by barring a change of service (using a new SIM).

Unlocking Technology:

Commonly, a locked phone will show a message if a restricted SIM is used, requesting the unlock code. On new phone models running Android software, the phone will show a message stating “SIM network unlock PIN” or “Enter Network Lock Control Key” if it is network locked. Windows phones are going to show the message, “This SIM card can only be used on specific networks. Contact your customer service center for the unlock code”. Several other handsets could display varying messages for example , "Enter special code" or "Enter unlocking code," or in some instances the phone may simply present a message saying that it is locked. Whenever a valid code is keyed in, the phone will display "Network unlocked” or “Network unlock successful”.


Phone makers have economic incentives both to enhance SIM lock security (which placates network providers and allows exclusivity discounts) as well as to weaken it (extending a mobile's overall appeal to buyers that typically are not interested in the provider that offers it). In addition, making it too hard to unlock a handset might make it a lot less desirable to mobile phone network service providers who have a legal liability to provide unlock codes for some devices or in particular countries.

Unlocking Services:

Certain organizations offer a permanent phone unlocking service . This service needs individuals who wish to unlock a handset to give their IMEI number to a service supplier and frequently they will also require the country and service provider the handset is locked to, frequently sent by email or entered on their web site. The supplier will then supply (at a cost to you) an unlock code for the handset. For many makes for example Nokia and Samsung a variety of services also deliver unique remote-unlocking software with instructions, when a cable connection is required to remove the SIM lock at home. Such organizations may email the unlocking code or software which will remotely unlock the device. The cost for unlocking a telephone will change according to the mobile phone network it's locked to and the mobile phone model itself, as every unlock code is unique to each individual handset.

Unlocking Service Providers:

Regrettably there are many of dodgy web sites operating in the cell phone IMEI unlocking industry. As a consequence it is advisable to ensure you find a trustworthy provider for these services. Do your due diligence and investigate every prospective suppliers before committing to submitting an order. In the case of on-line sellers, make sure they document their genuine business name and associated registration details (every legit organization has to be legally registered with all the official governing bodies within their country of origin) and make certain they give a genuine certified address and contact information on their web-site. Additionally make sure that any payments made are through legitimate sources for instance a recognized bank or financial institution using a debt or credit card, but do not ever make payment via a direct transfer because this provides no fiancial protection. To assist with the search for a trustworthy supplier, we've provided a checklist just below (and in no specific order) of a number of genuine organizations currently offering such services.

Reputable Mobile Phone IMEI Unlocking Service Providers: