The Telerik.OpenAccess.Adonet2 assembly is not being used in Sitefinity from 4.2 +. The file was used by earlier versions of Open Access, but it is not required anymore. Because of the new version of Open Access and the improved performace of the Sitefinity LINQ parser we managed to remove the ado.net dependancy and the ado.net dll is no longer needed.
However if you are using a version of Sitefinity that is lower than 4.2, please ensure that the dll version matches the one that is being distributed your particular Sitefinity version. If your application is looking for the 2010.3.1125.1 it seems that a control or module is referencing the old one. Please provide the newest version of the dll for your project and re-add the reference to it.
the Telerik team
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