Exporting symbols in a .exe for external DLLs

Hello, 

I am facing a strange problem.

Basically, I have my application that loads a DLL (I developped).

My DLL exports functions I can call from my application : OK

I would also like to call functions of my application from my DLL : it does not work.

To do that, in my DLL, I call :

HMODULE hModule = GetModuleHandle("application.exe");
FARPROC hFunc = GetProcAddress(hModule, "appFunction"); // (defined by : void __declspec(dllexport)  appFunction(void) in my application

hModule is non-zero but hFunc is NULL. When I use a tool to see exported symbols by application.exe, there is none.

So my question is : Can I export symbols from a .exe with LabWindows 8.5 ?

thanks in advance