Have a problem,I bought an iphone 4 and I need to know how to activate it when its used and has the owners old id and password
If iPhone has IOS 7 on it then without the owner's Apple ID & password it's useless to you. Get a refund.
Read and make sure the seller done all these:
You can't without the credentials used to lock it. Return it and get your money back if whoever you bought it from can't remove the lock. It's probably stolen.
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