[path]\plugin.dll is not a valid Win32 application

I followed the guide at http://www.juce.com/doc/tutorial_create_projucer_basic_plugin

When trying to build the app, I get a popup saying:

"Unable to start plugin.dll" 

"plugin.dll is not a vaild Win32 application"

This is in Visual Studio 2015. I'm on Windows 10 64 bit.

Are you familiar with plugins / .dlls? They're not executable directly, but rather dynamically linked libraries (DLL) - You'll need something to host it... Like a plugin host