Note: This article was originally published in 2012. Some steps, commands, or software versions may have changed. Check the current Exchange documentation for the latest information.
Description: Forefront TMG detected changes in Microsoft Exchange Server or Microsoft Forefront Protection configuration, and reapplied the e-mail policy configuration. After reading about it this issue is due at times because of locales used that are not standard EN-US, and Microsoft has also released a hotfix which you can use to address it. In my case I only removed Forefront protection for Exchange and that did the trick.