Does anyone know what this means?
1> Generating Code...
1>BlankWindowDXbaseImpl.obj : error LNK2019: unresolved external symbol "public: __thiscall DXBase::DXBase(void)" (??0DXBase@@QAE@XZ) referenced in function "public: __thiscall BlankWindowDXBaseImpl::BlankWindowDXBaseImpl(void)" (??0BlankWindowDXBaseImpl@@QAE@XZ)
1>BlankWindowDXbaseImpl.obj : error LNK2019: unresolved external symbol "public: virtual __thiscall DXBase::~DXBase(void)" (??1DXBase@@UAE@XZ) referenced in function "public: virtual __thiscall BlankWindowDXBaseImpl::~BlankWindowDXBaseImpl(void)" (??1BlankWindowDXBaseImpl@@UAE@XZ)
1>main.obj : error LNK2019: unresolved external symbol "public: void __thiscall DXBase::shutdown(void)" (?shutdown@DXBase@@QAEXXZ) referenced in function _wWinMain@16
1>main.obj : error LNK2019: unresolved external symbol "public: bool __thiscall DXBase::initalize(struct HINSTANCE__ *,struct HWND__ *)" (?initalize@DXBase@@QAE_NPAUHINSTANCE__@@PAUHWND__@@@Z) referenced in function _wWinMain@16
1>C:\backup\development\directXworkspace\BlankWindow\Debug\BlankWindow.exe : fatal error LNK1120: 4 unresolved externals