Most probably you have deleted the Telerik.Sitefinity.dll from _EmptyProject\bin
or from the bin of the project you are trying to run. Another reason is a permission issue that blocks the request to the dll. If the problem persists, please open a support ticket and send Sitefinity.exe and the license file you use. You can attach them to an external link or send me FTP credentials. I will get the project manager and run it locally.
Also , make sure that you are not trying to run the project from your desktop.
the Telerik team