Visual Studio 2015 Native Unit Test Can't Find 3rd Party .DLL

I'm using Visual Studio 2015. I created a .dll and would like to write a Unit Test. I Created a New Project using the Native Unit Test Project found in the

File | New | Project...

Visual C++ | Test | Native Unit Test Project

All works until I run it. The code requires using the SQLite .dll (sqlite3.dll). When I run the test, I get the error dialogbox:

The program can't start because sqlite3.dll is missing from your computer. Try reinstalling the program to fix this problem.

I have the .dll so I suspect the message saying it is "missing" really means "unable to find".

I've attempted a lot of things to fix this, including editing the following Property Pages values:

Configuration Properties:

Debugging | Environment VC++ Directories | Executable Directories

These changes to my project make no difference. Does anyone know how to get VS2015 testing to find 3rd party .dlls?

Thx.