When running an older version of Sitefinity under Windows 10, the Telerik enhancer.exe requires the .NET Framework 3.5 to be installed. By default Windows 10 does not come with the .NET Framework 3.5 so you will need to install it. Windows 10 comes with the .NET Framework 4.6 installed by default.
Here is the error for future reference:
Microsoft.Build.Utilites 2.0.0 was not able to reference the assembly Telerik.Sitefinity.OpenAccess in \packages\Telerik.DataAccess.Fluent.2015.3.926.1\tools\enhancer\enhancer.exe
