I am sorry for the inconvenience you are experiencing.
Generally, the error appears when you consume a model that was not postprocessed by the Data Access Enhancer tool
Going through the provided information I understand that you are using Data Access Q1 2016 and that you have a web application in your hands. To complete the picture and to troubleshoot the situation I would kindly ask you to provide me with a few additional details:
1. Could you confirm that you are using the Data Access NuGet packages?
2. If so, could you confirm that the project that holds your model has the Telerik.DataAccess.Core package installed on it?
3. If so, could you check if the following clause is available in the XML representation of the project that holds the model?
I'm looking forward to hearing from you.
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