27th
“A valid signing identity matching this profile could not be found on your keychain”
Once a year your iPhone Development Certificate expires and you have to to the Certificate Hamster Dance. It’s easy to request and install a new certificate (“developer_identity.cer”), but you must edit your existing provisioning profiles on the program portal to refer to the new certificate, then update and download each provisioning profile as well.
In hindsight, it makes sense. Your old provisioning profile (e.g. “nuthatch.mobileprovision”) refers to a developer certificate you just replaced. So that signing identity can no longer be found. The new profile includes the new certificate, and all is good again. For now.
It’s a shame the error messages are so useless. I understand this is all fixed in Xcode 4.0 but googling the phrase “A valid signing identity matching this profile could not be found on your keychain” returns a lot of noise. The final hint (duh!) came from http://bit.ly/valid-signing-identity
