I tried to add my iPhone to Xcode4 to test my Application on it. I added the device in the Apple Developer-Center and downloaded the Provision-Profile. We pay 99$ per month for the account and I'm not the only person who use this account. So there is already an "older" certificate present which I tried to add to my keychain-manager. But I see a red-text above it (translated from german) "This certificate has been signed by an unknown instance.".
In my XCode-Device Manager in the Provisioning-Section there's also an error: "XCode could not find a valid private-key/certificate pair for this profile in your keychain."
I really don't understand what I have to do now. These keys may really not exist in my keychain, I can't find them. So how I have to create them know and how can I use them if there is already one certificate in the Apple Dev-Center?