I believe that many iPhone users may encounter problems with the phone show not being activated. You first need to confirm whether there is a prompt "No SIM card installed", confirm that there is no problem with the phone sim. This article will provide some solutions for could not activate iPhone unknown error.
Way1: The Phone Has a Prompt"No SIM Card Installed"
If the phone has a prompt "No SIM card installed" or no service, then you can according to How to Fix iPhone 7 No Service Issue.
With this action, you can verify that your iPhone is not activated.
Way2: Follow the steps below to fix Can't activate your iPhone 6
Check the list on the "System Page". If the iOS device activation box is not green, try activating your iPhone later.
If you are asked to enter a password when you activate your iPhone, please enter your password.
2.1 Restart your iPhone;
If you are using a cellular data connection, connect to a Wi-Fi network instead;
Activate your iPhone 6 using iTunes as follows:
2.2 Make sure you have the latest version of iTunes;
2.3 Check if your computer has an Internet connection;
2.4 Open iTunes on your computer. Connect your iPhone to your computer using the data cable;
2.5 Wait for iTunes to detect and activate your iPhone;
If iTunes shows "Create New Apple ID"or "restore from backup", it means iTunes has activated your iPhone.
If the error in iTunes indicates that the SIM card is not compatible, please contact your carrier.
Way3: Fix Cannot Activate iPhone after iOS Update
Here are some effective ways to fix iOS 11/12 activation errors and get your iPhone up and running.
3.1 Wait and try again
If you are unable to activate your iPhone because the activation server is temporarily unavailable or inaccessible, it is best to wait. It may be that the server on the Apple side is down or busy and has not processed the request. You should wait a few minutes and try again.
3.2 Force restart the device
This is the easiest way to resolve iOS issues caused by software crashes, software bugs or software conflicts. Simply press and hold the sleep/wake button and the home button (the volume down button on iPhone 7 or higher). Press and hold the button for at least 10 seconds and release the button when the Apple logo appears.
3.3 Check the network connection
It is possible that your network is preventing you from successfully activating your iPhone. Connect to a different Wi-Fi connection. Or if you are using a cellular data connection, try connecting to a reliable Wi-Fi network.
3.4 Unlock/lock SIM status
If you try to activate another carrier on a locked iPhone. You have recently purchased an iPhone from your carrier, it will not be activated until the carrier unlocks it. In this case, please contact your carrier and ask them to unlock your iPhone and SIM card.
3.5 Reactivate your iPhone using iTunes
If you still can't activate your iPhone after the upgrade, try re-activating iTunes by following the steps below.
Restart iPhone>Connect to Phone with iTunes>Select your device, you can see "Activate your iPhone" on iTunes > Enter your Apple ID and password > Click to continue to activate your iPhone.
Way4: Activate iPhone 6 Without SIM
Activate and use the iPhone without a SIM card so that you can use many phones at the same time without having multiple phone numbers.
4.1 Activate your iPhone with someone else's SIM card
Here's how to activate your iPhone:
Get SIM card on other iPhone
Put it on your iPhone
Complete common setup options, including logging into a Wi-Fi network
Waiting for iPhone activation
You can now use your iPhone; you can't make calls (unless you use Skype, Facebook Messenger, Whats App or FaceTime)
4.2 Activate your iPhone with iTunes
Check if iTunes is up to date, or if you don't have iTunes yet, please download it for free from Apple store;
After installing iTunes, we connect the unactuated iPhone or iPad to the computer with the data cable;
After the connection is completed, iTunes will automatically detect the device. When it detects that the device is not activated, a registration window will pop up to guide the user to activate the device;
The activation step for the new iTunes device is over and your iPhone or iPad is ready for use.
4.3 Jailbreak your iPhone
If all else fails you can always attempt to jailbreak your iPhone. This does void your warranty, but if you've got an old iPhone that's carrier-locked, it might be the best way to get it working again.
Way5: Real Case for How to Activate an iPhone 6 plus
iPhone model: iPhone 6 Plus
Symptom: The phone cannot be activated
After receiving an iPhone description, it cannot be activated after upgrade the IOS,show that the activation failed.
The first thing that can't be activated like this is that it expands capacity before upgrading the IOS11 system, because the previous iPhone of the IOS11 system only verified the serial number, and the IOS11 system must verify the Bluetooth WIFI.
Disassemble found that its hard disk has not been moved, query his serial number is also matched, but IOS12 also needs to verify an NFC, we remove NFC.
Activation succeeded after replacing an NFC chip.
How to Fix Your iPhone Broken parts:
You can purchase all the mobile phone repair parts you need at reasonable prices in the GEMWON online store, including Samsung/Huawei/iPhone/XIAOMI display, battery and camera replacement accessories.
The above is the detailed solution to your iPhone could not be activated. These methods are applicable to all versions of iPhone 6/7/8/X and plus. If you still do not solve the problem that the iPhone can’t be activated according to the above, then you need to ask for the apple store.
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