Code sign error during archiving the proejct in xcode

I am trying to build ipa for the purpose of testing using Ad Hoc. When I tried to archive this is the error I am getting

Code Sign error: The identity 'iPhone Developer' doesn't match any valid certificate/private key pair in the default keychain

I dint create any keys. Do I need to create one? Is there any good pa开发者_StackOverflowge to follow the steps? And which is the simplest way for testing iphone app?

FYI I am using xcode 4

Thank you

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From HOWTO: Obtaining your iOS Development Certificate:

In the ‘Certificates’ section of the iOS Provisioning Portal, you can request individual iOS Development Certificates. All iOS applications must be signed by a valid certificate before they can be run on an Apple device. In order to sign applications for testing purposes, Team Members need an iOS Development Certificate.

A digital identity is an electronic means of identification consisting of a secret "private key" and a shared "public key". This private key allows Xcode to sign your iOS application binary.