Based on the provided information, I assume that your project consumes the Telerik Data Access NuGet packages and that recently it was upgraded to consume the latest version of the packages.
If this is the case, you need to check the following clause in the .csproj file of the project that holds the model:
This is the path to the location where the Data Access Enhancer tool should reside. With a successful installation of the latest Fluent NuGet package, YYYY.Q.MDD.X should be 2015.2.624.1; when you navigate to this location on your local storage, you have to find the enhancer.exe file.
I also suggest to you to check the references to the Telerik.OpenAccess.* assemblies in your project. They should point to version 2015.2.624.1 as well.
In order to avoid such errors in the future, you need to restart Visual Studio after the upgrade of the Data Access NuGet packages.
If the scenario on your side is not the outlined one, it would be helpful to provide me with the details about the setup.
I hope this helps. Let me know how the things on your side are.
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