After upgrade of OSX, Apple's iTunes Producer app will not start. It gives an error:
"We are unable to retrieve your password from the security keychain."
The keychain is upgraded by the OSX update.
Reset the app with:
1. Navigate to the Terminal app.
Applications --> Utilities --> Terminal
2. Run the following command
(no need for sudo)
$ defaults remove com.apple.iTunesProducer ITunesUsername
3. Return to Applications and launch iTunes Producer again.