The Telerik.Sitefinity.dll is part of every Sitefinity based project. You can create a new Sitefinity Project using our Project Manager and locate the assembly in the bin folder. here is a link
to the documentation on how to achieve that. As far as the SDK is concerned you can find the assemblies there in the C:\Program Files (x86)\Telerik\Sitefinity 4.1\SDK\Content\Common\Dependencies folder where they are referenced for our samples. Please don't move or delete any of the assemblies in this folder as it might affect the SDK Samples.
Thank you for contacting us and please let me know if you need further assistance.
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
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