sim not valid

A SIM lock, simlock, network lock, carrier lock or (master) subsidy lock is a technical restriction built into GSM and CDMA mobile phones by mobile phone manufacturers for use by service providers to restrict the use of these phones to specific countries and/or networks. This is in contrast to a phone (retrospectively called SIM-free or unlocked) that does not impose any SIM restrictions.
Generally phones can be locked to accept only SIM cards with certain International Mobile Subscriber Identities (IMSIs); IMSIs may be restricted by:

Mobile country code (MCC; e.g., will only work with SIM issued in one country)
Mobile network code (MNC; e.g., AT&T Mobility, T-Mobile, Vodafone, Bell Mobility etc.)
Mobile subscriber identification number (MSIN; i.e., only one SIM can be used with the phone)Additionally, some phones, especially Nokia phones, are locked by group IDs (GIDs), restricting them to a single Mobile virtual network operator (MVNO) of a certain operator.
Most mobile phones can be unlocked to work with any GSM network provider, but the phone may still display the original branding and may not support features of the new carrier. Besides the locking, phones may also have firmware installed on them which is specific to the network provider. For example, a Vodafone or Telstra branded phone in Australia will display the relevant logo and may only support features provided by that network (e.g. Vodafone Live!). This firmware is installed by the service provider and is separate from the locking mechanism. Most phones can be unbranded by reflashing a different firmware version, a procedure recommended for advanced users only. The reason many network providers SIM lock their phones is that they offer phones at a discount to customers in exchange for a contract to pay for the use of the network for a specified time period, usually between one and three years. This business model allows the company to recoup the cost of the phone over the life of the contract. Such discounts are worth up to several hundred US dollars. If the phones were not locked, users might sign a contract with one company, get the discounted phone, then stop paying the monthly bill (thus breaking the contract) and start using the phone on another network or even sell the phone for a profit. SIM locking curbs this by prohibiting change of network (using a new SIM).
In some countries, SIM locking is very common if subsidized phones are sold with prepaid contracts. It is important to note, however, that the technology associated with the phone must be compatible with the technology being used by the network carrier. A GSM cell phone will only work with a GSM carrier and will not work on a CDMA network provider. Likewise, a CDMA cell phone will only work with a CDMA carrier and will not work on a GSM network provider. Note that newer (2013+) high end mobile phones are capable of supporting both CDMA and GSM technologies, allowing customers to use their mobile devices on any network. Examples of these mobile devices are the Apple iPhone 5c, 6 and newer, Motorola's G4, G5, X Pure, Samsung's Galaxy S6, S7, S8 smart phones, mostly phones based on a Qualcomm Snapdragon chipset or radio.
In some jurisdictions, such as Canada, Chile, China, Israel, and Singapore, it is îllégâl for providers to sell SIM locked devices. In other countries, carriers may not be required to unlock devices or may require the consumer to pay a fee for unlocking.
Unlocking the phone, however, is almost universally legal. Additionally, it is often legal for carriers to force SIM locks for certain amounts of time, varying by region.

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  1. 2

    SIM NOT VALID. AT&T KDDI JAPAN LOCKED

    Hello mga sir, baka pwede naman patulong po, Pano e unlock. SICKW.COM IMEI Check Model Description: IPHONE 6 PLUS SPACE GRAY 64GB-JPN Model: iPhone 6 Plus 64GB Space Gray MM-TD [A1524] [iPhone7,1] IMEI: 354377066338876 MEID: 35437706633887 Serial Number: F2LNPRBMG5QV Warranty Status: Out Of...
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    IPhone 6 not valid sim

    Halo mga ka PHC pa help naman po nung iphone 6 ko, sim not valid po kasi,,. nakalagay SMART 36.1 pero nag lagay ako ng tnt&smart lumabas sim not valid., please help namn po
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    Closed SIM NOT VALID

    Saan nakaka bili nang GPP LTE for Iphone 6 plus Yung working sa IOS 12.4 latest. Thanks po sa sasagot.
  4. M

    Closed iPhone SIM NOT VALID help..

    Magandang gabi sa inyo mga kababayan 🙂 Hoping na may makakapag tulong sakin. Bumili ako ng LTE sim para sa kaibigan ko para magupgrade na siya from 3G. Nung pinalitan namin yung sim card, kailangan palang iactivate pero hindi pwede kahit sundin namin yung mga tutorial sa YøùTùbé. May GPP chip...
  5. S

    Closed Sim not valid

    Kapag po ba bumili ng factory unlocked iphone may possibility na mag globe locked kapag di ka nag papalit ng sim kasi nag Sim not Validyung result nung nag try akong palitan sya ng sim.
  6. C

    Closed Sim not valid after factory reset

    Pa help naman po. Sim not valid lumalabas after ko ipa factory reset/reformat ung iphone 6 ko. Kahit palitan ng sim ganyan pa din. Nag try nako lahat ng possible solutions sa google pero yan pa din lumalabas.
  7. M

    Closed Iphone 5s gpp sim not valid

    mga paps, patulong naman po. may iphone 6+ tsaka iphone 5s po ako. lahat gpp. pero hindi ko maactivate yung sa iphone 5s. lahat ng gpp chip gumagana pag nilagay ko sa iphone 6+. pero pag nilipat ko sa iphone 5s(parehas na sim). sim not valid ang nakasulat. :(( badly need help.
  8. T

    Closed Help please. iphone 5s (gpp) na reset, now locked.

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    Closed [help] sim not valid after reset

    Hello guys , yep , i have iPhone 6. GPP siya, at nireset ko siya. Hindi ko alam na di pala pwede yun. So yun , SIM not Valid na ang nakalagay. Is there any way para maayos siya without buying new gpp lte chip ? Help pleaseee. Kung pag-unlock sya , paturo naman ohh. Send Heeeelp. Thanks !!
  10. M

    Closed Ios 11.1 gpp lte xsim etc

    Para makatulong naman based on experience. Based on Iphone 6 ios 11.1 locked to sasktel Canada. Gpp lte gamit ko before sa ip6 ios 11.1 working pa rin kahit upgraded na pero 3g lang na sim. Nareset ko and change sim gumana naman until ginalaw ng pinsan ko ang setup ng gpp nagstuck na ko sa...
  11. D

    Closed Iphone sim not valid/supported sa gpp (and meron din daw sa mga factory unlocked?)

    sino sino po nakaexperience nito? Ano po ang mga solutions, or options natin ngayon? Thanks My iPhone 6 na gpp unlock nagkakaganito kapag ibang sim na ang gagamitin.
  12. W

    Closed Iphone 4s Sim Not Valid

    Guys pa help naman po with my Iphone 4s. After ko input yung Carrier Code ni Globe (5150201) tapos pagka restart nya, lumalabas na SIM not Valid. I tried inserting other sim card pero same pa din. Is there a way to undo yung ginawa ko? Naku.. :( Patulong naman po sa may alam kung ano need ko...
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