Linker Errors

I have a dll I’m trying to add functionality to, this file already opens a dialog window. I want to call another dialog. I want to call another dialog in the constructor of this one, which I would think nominally is really easy.

resource editor>add resource>new dialog
then I added the buttons and edit boxes I wanted. Then right clicked on the dialog in the resource editor and added a class for it. So far to this point everything built fine.

Now:

Linking...
.obj : error LNK2005: "public: static struct CRuntimeClass * __stdcall CSGOptionsBlackBoxClientDlg::GetThisClass(void)" (?GetThisClass@CSGOptionsBlackBoxClientDlg@@SGPAUC RuntimeClass@@XZ) already defined in TraderDialog.obj
SGOptionsBlackBoxClientDlg.obj : error LNK2005: "public: virtual struct CRuntimeClass * __thiscall CSGOptionsBlackBoxClientDlg::GetRuntimeClass(void) const " (?GetRuntimeClass@CSGOptionsBlackBoxClientDlg@@UBE PAUCRuntimeClass@@XZ) already defined in TraderDialog.obj
SGOptionsBlackBoxClientDlg.obj : error LNK2005: "public: __thiscall CSGOptionsBlackBoxClientDlg::CSGOptionsBlackBoxCli entDlg(class CWnd *)" (??0CSGOptionsBlackBoxClientDlg@@QAE@PAVCWnd@@@Z) already defined in TraderDialog.obj
SGOptionsBlackBoxClientDlg.obj : error LNK2005: "public: virtual __thiscall CSGOptionsBlackBoxClientDlg::~CSGOptionsBlackBoxCl ientDlg(void)" (??1CSGOptionsBlackBoxClientDlg@@UAE@XZ) already defined in TraderDialog.obj
SGOptionsBlackBoxClientDlg.obj : error LNK2005: "protected: static struct AFX_MSGMAP const * __stdcall CSGOptionsBlackBoxClientDlg::GetThisMessageMap(voi d)" (?GetThisMessageMap@CSGOptionsBlackBoxClientDlg@@K GPBUAFX_MSGMAP@@XZ) already defined in TraderDialog.obj
SGOptionsBlackBoxClientDlg.obj : error LNK2005: "protected: virtual struct AFX_MSGMAP const * __thiscall CSGOptionsBlackBoxClientDlg::GetMessageMap(void)co nst " (?GetMessageMap@CSGOptionsBlackBoxClientDlg@@MBEPB UAFX_MSGMAP@@XZ) already defined in TraderDialog.obj
SGOptionsBlackBoxClientDlg.obj : error LNK2005: "protected: virtual void __thiscall CSGOptionsBlackBoxClientDlg::DoDataExchange(class CDataExchange *)" (?DoDataExchange@CSGOptionsBlackBoxClientDlg@@MAEX PAVCDataExchange@@@Z) already defined in TraderDialog.obj
.\NYSPeg.def(4) : warning LNK4017: DESCRIPTION statement not supported for the target platform; ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "public: static struct CRuntimeClass * __stdcall CSGOptionsBlackBoxClientDlg::GetThisClass(void)" (?GetThisClass@CSGOptionsBlackBoxClientDlg@@SGPAUC RuntimeClass@@XZ) already defined in TraderDialog.obj; second definition ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "public: virtual struct CRuntimeClass * __thiscall CSGOptionsBlackBoxClientDlg::GetRuntimeClass(void) const " (?GetRuntimeClass@CSGOptionsBlackBoxClientDlg@@UBE PAUCRuntimeClass@@XZ) already defined in TraderDialog.obj; second definition ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "public: __thiscall CSGOptionsBlackBoxClientDlg::CSGOptionsBlackBoxCli entDlg(class CWnd *)" (??0CSGOptionsBlackBoxClientDlg@@QAE@PAVCWnd@@@Z) already defined in TraderDialog.obj; second definition ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "public: virtual __thiscall CSGOptionsBlackBoxClientDlg::~CSGOptionsBlackBoxCl ientDlg(void)" (??1CSGOptionsBlackBoxClientDlg@@UAE@XZ) already defined in TraderDialog.obj; second definition ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "protected: static struct AFX_MSGMAP const * __stdcall CSGOptionsBlackBoxClientDlg::GetThisMessageMap(voi d)" (?GetThisMessageMap@CSGOptionsBlackBoxClientDlg@@K GPBUAFX_MSGMAP@@XZ) already defined in TraderDialog.obj; second definition ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "protected: virtual struct AFX_MSGMAP const * __thiscall CSGOptionsBlackBoxClientDlg::GetMessageMap(void)co nst " (?GetMessageMap@CSGOptionsBlackBoxClientDlg@@MBEPB UAFX_MSGMAP@@XZ) already defined in TraderDialog.obj; second definition ignored
SGOptionsBlackBoxClientDlg.obj : warning LNK4006: "protected: virtual void __thiscall CSGOptionsBlackBoxClientDlg::DoDataExchange(class CDataExchange *)" (?DoDataExchange@CSGOptionsBlackBoxClientDlg@@MAEX PAVCDataExchange@@@Z) already defined in TraderDialog.obj; second definition ignored

Any idea what this means…. It seems to be the same thing over and over.