From the ADO.NET Team blog:
Late last week, after bits had been finalized, we found a bug in the ADO.NET Entity Data Model Wizard that shipped with Visual Studio “Orcas” beta 1. The problem has now been corrected.
Please download and install the patch available at: http://www.microsoft.com/downloads/details.aspx?FamilyID=f69e9eb8-0ebd-4fba-a4cc-2050297ba75b&displaylang=en to fix the problem.
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