When attempting to install the Connect browser plugin on a Mac the following error occurs:
The domain/default pair of (kCFPreferencesAnyApplication, AppleLanguages) does not exist
This happens because the Connect plugin now supports multiple languages (Simplified Chinese, Japanese, French and Spanish in addition to English) and in attempting to detect the default language to use for the installation no entry is found in the preferences for this user.
This can be resolved by editing System Preferences. For older Mac systems select the Language and Text icon and add US English to the Languages list using the check box. For newer systems select the Language and Region icon and add English to the list, making it the primary language.