How to Unlock a Locked SIM Card Manually by Amy McClain. If your phone uses a SIM card to operate, you can activate a security feature called a SIM PIN. The SIM PIN protects your SIM card from unauthorized use, and must be entered in order to use your phone. Enter it incorrectly three times and your SIM card becomes locked. Sprint says that it also has to be a phone that is domestic SIM Unlock capable for the domestic United States. As with other carriers, the device cannot have been reported as lost, stolen or blocked.
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In this Simple Step by Step Guide I will show you how to fix the 'No Sim Card Installed', 'Invalid Sim' or 'Sim Card Failure' Error on iOS. This issue is common across most iPhone models and appears under various circumstances. These errors can severely prevent you from using your phone by blocking you from placing calls, browsing the internet or sending text messages. There are various reasons why these error messages appear and in this video, we collected every possible way to fix it in an easy to follow format so you can fix your iPhone yourself without having to pay a repair shop or visit the apple store.These solutions have been found effective for iPhone 4, iPhone 4s, iPhone 5, iPhone 5s, iPhone 5c, iPhone 6, iPhone 6 Plus, iPhone 6s, iPhone 6s Plus, iPhone SE, iPhone 7 and iPhone 7 Plus. Aswell as iPadinvalid sim card fixhow to fix invalid sim cardinvalid siminvalid simiphone 6 no sim cardno sim iphone 6iphone invalid simno sim card iphoneiphone 7 no sim cardiphone 7 invalid simno sim card installed iphoneiphone 6 sim card problemno sim cardno sim iphoneinvalid sim card fix iphoneThanks for watchingJoshua Wilson (MacCrunch Author)Visit us:MacCrunch on Facebook:MacCrunch on Twitter.
SIM CardsMost cellphones you buy have SIM cards installed in them. SIM cards are memory chips used in cellular devices to store your account's information, your cellphone number, your phone book, text messages and other data. Because they contain such sensitive information, avoid removing them from the phone unless absolutely necessary.Unlocking a SIM is often done to change the service carrier or to remove the phone for sale. The new owner will require an unlocked phone to install and use their own SIM card. Locked SIM CardsUnless you specifically purchased an unlocked phone, your phone is likely to have a SIM lock on it. This feature prevents you from taking a particular provider's phone and using it on another network. The lock helps keep devices on their originally assigned networks.
However, most devices can be unlocked using a SIM unlock procedure. Unlock ProcedureYou can remove the SIM lock by performing an unlock procedure on the phone. Although the specific unlock instructions differ according to your phone model, the procedure consists of obtaining an unlock code from your existing mobile provider. You can also buy a code online if the provider is unable to give it to you. After you obtain the unlock code, you install another network's SIM card, power on the phone and then enter the unlock code when prompted. Network CompatibilityJust because you unlock your phone doesn't mean that you can use the phone on any network. The SIM card for the new network must compatible with the network your phone currently supports.
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The major networks – T-Mobile, AT&T, Verizon and Sprint – are either GSM or CDMA networks. Therefore, if your phone is a GSM phone, you can't use it on the Sprint network, as Sprint operates a CDMA-based network. International SIM CardsOne common reason for unlocking a phone is to use the device internationally. Most countries have their own SIM cards and you can purchase a SIM and a phone plan in a different country while visiting. In this case, you must unlock the phone and actually remove and replace the old SIM card with the new SIM card to gain compatibility on the country network.For example, Mexico uses TELCEL service for their entire country. If you unlock your phone, you can replace the SIM with a TELCEL card while visiting and enjoy a data plan with local and even international calling at a much reduced rate. Using this system is common for long term travel where alternating service plans according to location is useful.