I am sorry to hear that you are experiencing issues with Data Access. Following are the answers to your questions:
The Telerik.OpenAccess reference error
It is possible that the assembly is a dependency of some other component in your application. For example:
a) If you use the persistent classes generated by Data Access when you consume Entity Framework and these classes reside in a separate class library (along with the rest of a Data Access model), than this class library will require the Telerik.OpenAccess assembly implicitly.
b) If your MVC application utilizes the Telerik Reporting tool. Reporting internally uses Data Access for retrieving data and again requires the Telerik.OpenAccess assembly implicitly.
In any of these cases, you need to isolate which component of the application refers to the assembly and to deal with it accordingly, in order for the error to be resolved.
On your development machine, the application worked because Data Access was installed.
The failure of Visual Studio to load EntityDiagramsPackage
In order to resolve this error you need to run the devenv / setup
command in Visual Studio's Developer Command Prompt
I hope this helps. Let us know how the things on your side are.
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