How to unlock iPhone 4 after updating to ios 7?

Question

iPhone

Uncle gave him his iPhone 4. The phone was given to him at work with a contract, a contract for some European operator. After the expiration of the contract and leaving the old job, the SIM card was lost. I used the phone like an iPod: watch videos, surf the web, music. After updating to ios 7, the phone requires activation through the network of the operator for which the contract was. Is it possible to somehow restore the phone?
There are no Apple service centers in the city, when describing a problem on apple.com/support/ - they send a link to AppleID, which must be opened from an apple device, but the device itself does not turn on!

Answer 1

You need to ask your uncle if he can call the operator to which the phone was registered, after authorization (you will need an ID from the back), ask him to unblock it, since the contract has ended - it will not cost anything. Rarely, but it happens that this is already done automatically.
Next, you need to download apple itunes to your computer (I assume that this has already been done), be sure to insert the SIM card of your provider, and it will be something like restoring the default settings in itunes, after another reboot (if the phone is unlocked by the operator) you will be asked to create your own id and with you can use it (done already more than once :))