I had problems while "archiving" my app. I think there are invalid profiles because of iPhone Update to 5.1 and XCode update to 4.2.2.
I\'ve taken now more
@Takoi's answer is correct. However, with my latest version of Xcode, there is no TEAM option in the Devices section of the Organizer. I had to do the following instead to refresh the credentials:
Xcode will now refresh the updated credentials, and you can proceed to validate or distribute your app.
Hope this helps!