Project Test raise an error when I added the reference to Arduino Project

I have two projects in my Visual Studio Community 2013 solution.

I created a project for Arduino, and create another project for Test. When I run the project tests without adding the Arduino project reference, it run ok, but when I add the Arduino project reference I get it error:

LNK1561: entry point must be defined D:\VisualStudioArduino\PrinterProject\LINK PrinterProject

What is the entry point for Arduino project?

It does not generate any file like a dll or main file?

What can I do to solve this error?

UPDATE

I also tried this configuration in the Arduino Project but I get the same error:

Properties -> Linker -> System -> SubSystem to "Windows (/SUBSYSTEM:WINDOWS)"