I'm using Xcode 4.3.1 on Mac OS X 10.7.3 trying to provision to iOS 5.1 phone. First I used the Development Provisioning Assistant to create a provisioning profile. After dragging/installing the profile in Organizer, it says "valid signing identity not found". I continued with the Development Provisioning Assistant, got a new Development Certificate, installed it. But it didn't help. It's still "valid signing identity not found". After reading this topic on google and other people's solutions, I deleted all keys in Keychain Access, walked through the Development Provisioning Assistant again, did everything it said, but still didn't fix the problem. So I thought I needed a fresh start again. I deleted all provisioning profiles, certificates, keys. Then I redid everything, but no use. I also tried "Add to portal" in the Organizer, which only generated 4 certificates but still no keys.
Should I restart my machine? Just kidding.
I've been there a couple of times where you are right now. So I tried to understan what was going on and documented it here (Understanding iOS Code Signing) (warning: tl;dr).
Its easy to make mistakes while "following" the steps listed on the portal
, and understanding it can help you identify what went wrong.
Here's a quick checklist for you before you go reading the whole thing:
If you are doing this and still face the problem, you should try 'understanding' then :).