現象：
The Entity Framework provider type 'System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer' registered in the application config file for the ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application.
原因：
在測試環境是有EntityFramework.SqlServer.dll 而部署的時候，這個dll沒有被放到部署的bin文件夾中。
解決：
從測試環境的obj的文件夾下拷貝到部署所在的bin目錄下。