This article describes how to resolve the 'Sim card invalid' error on iPhone upon activation.

Activation error
Activation is permission to use a phone with a new SIM card. The error will block the phone if there is a malfunction in the smartphone or an invalid iphone SIM card is installed.
The 'SIM card is invalid' error iphone 5s blocks the phone:
- after replacing the SIM card;
- after system recovery;
- after update;
- when you turn on a new device for the first time.

Error reasons
Physical damage
By inserting a SIM card into the iphone 6, you can break the connector. Damage reduces the sensitivity of the contacts and can be the cause of the iPhone 6 'Sim card invalid' error upon activation.

Program crash
The smartphone may not see the SIM card due to an error during the firmware.
If the software installation failed, then after the update IOS the iPhone says 'SIM card is invalid'.

Telecommunications operator
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Locked iPhone is the binding of a smartphone to one mobile operator. If the SIM card on iPhone 6 is invalid, then the phone has Sim-Lock. Such a blocking interferes with activation, so the iPhone writes that the SIM card is invalid.

Apple recommends
All devices brought from abroad have Sim-Lock (lock). If the phone was purchased at Apple Store, then contact the store's support service or follow the step-by-step instructions from the official website Apple.
- Make sure the tray is closed all the way.
- The latest version is installed iOS.
- Your Sim-card is activated.
- Reboot your device.
- Restore the firmware via iTunes.

Unlock iphone
Unlock is the process of unbinding from an official operator. After unlocking the phone works with other mobile operators. The service is paid and will take about a month.
Contact the operator to which the smartphone is linked. Enter IMEI to unlock the machine.
Turbo-SIM
Turbo-SIM is a card with a program that is installed in the tray along with a SIM card. It fixes the activation of the locked iPhone. It does not 'untie' the smartphone, but deceives the system.

R-Sim
This adapter allows you to untie your smartphone from a specific operator. Easily mounts to your phone tray and works with all smartphones Apple. Unlocking with an adapter allows you to use the phone immediately, therefore it requires a minimum of time and money.

Related Videos
See what to do if the iPhone 6 SIM card is invalid or iPhone 4 activation error. The video will help you quickly understand why the problem appeared and solve it.