If you have installed OpenAccess the project picks up the libraries from the GAC and changes the references path from the Libraries folder of Sitefinity where the correct OpenAccess assemblies are. You have to check whether the two assemblies Telerik.OpenAccess.dll
are referencing the Libraries folder of the Sitefinity installation that is located by default at C:\Program Files\Telerik\Sitefinity 4.0\Libraries.
The reasons is that Sitefinity is shipped with a custom version of OpenAccess due to the latency with which we do our development. We will do our best to make sure all future Sitefinity official releases are up to date with both the RadControls and OpenAccess in order to avoid such behaviors, and give you access to the latest product releases we have.
Please let me know whether the problem persists, and excuse us for the late response. We look forward to receiving your highly appreciated feedback.
the Telerik team
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