If you don’t take care, that the on premise and the 365 cloud Exchange of your organization is not well connected via a dedicated TLS connection, you will get into thsi issue when user display names are shown as email addresses. Read the following article, which discuss this issue and how to take care...
Thomas K.H. Bittner
Mon, Jan 9 2012
Filed under: Filed under: General, Exchange, Windows Server, Hosting, Microsoft Online Services, Managed Services, Active Directory, Certificate Service, Outlook, Windows Client, Cloud Computing, Dynamic Computing