Where to get private key for iPhone developer certificate?

Question

This may be very silly question but i can't find answer. I have just received provisioning profile and developer certificate from my customer, but i can't use it. Xcode organiser says Valid signing identity not found about this profile. I assume this is because the certificate i've received doesn't contain private key. So the question is where do i take that key? Should i ask the customer for it? But i think he may answer: "It's my private key and i cannot share it with you because it's private". So what should id do? Where to get it?

Solution 1

Ask your customer to provide the Private Key they might have used to create the Certificate and then the Profile was created, see image below from where to get the private key -> KeyChain

Solution 2

You definitely need the private key to sign your application. The person who create the certificate would have to export the certificate from the keychain (including the private key part) and give it to you.

Of course, a better solution would be if you could be added to the team and request your own certificate. But this is only possible for a company account and not if you signed up as an individual developer.