The exception you notice can present itself if you have either not cleared the nuget cache or if your nuget packages are an outdated version. If the cache is the issue, lease go to your %localappdata%\NuGet\Cache folder and dispose of its contents.
If this does not help, you can try re-installing the nuget packages. In order for you to do so you need to use the nuget console (see image). In the console you need to specify the project you are applying the nuget package as default project and the Package Resource should point to Sitefinity Nuget Server. When this is done add the following to the console:
Install-Package Telerik.DataAccess.Fluent -Version 2014.1.403.2
Ivan D. Dimitrov
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