After installing a clean sitecore 8 and the EXM module, I get the following exception when trying to create a new one-time-message:
Invalid object name 'dbo.Fact_AutomationStatesStatisticsByMessage'.
What's wrong?
Make sure that you run Sitecore.EmailExperienceManager.sql to create the necessary tables in the reporting database of your instance. The file is available in the Data folder.