c++ - error LNK2001: unresolved external symbol _IID_IDirectDraw2 -

i work piece of legacy code uses direct draw , i'm in rather embarrassing situation. not long ago i've updated system , had adapt new situation (loading ddraw.dll) , worked fine. today explored legacy solution uses classes (files) i've changed, i'm stuck above mentioned linking error. i've checked , compared project properties , seam fine.

this code directx initialization, "troublesome" code bold.

 typedef int (__stdcall *directdrawcreatefunc)(guid far* ,lpdirectdraw far* b, iunknown far* c);      /* init_directx:      *  low-level directdraw initialization routine.      */     int cdcutils::init_directx(hwnd allegro_wnd)     {        lpdirectdraw directdraw1;        hresult hr;        lpvoid temp;        hinstance ddraw = loadlibrary("%windir%\system32\ddraw.dll");        if(ddraw== null)        {            return -1;        }        _ddrawlib =ddraw;     directdrawcreatefunc ddfunc = (directdrawcreatefunc)getprocaddress(ddraw,"directdrawcreate");     if(ddfunc)     {      /* first have set directdraw1 interface... */        hr = ddfunc(null, &directdraw1, null);        if (failed(hr))           return -1;     }         ///* first have set directdraw1 interface... */        //hr = directdrawcreate(null, &directdraw1, null);        //if (failed(hr))        //   return -1;         //...then query directdraw2 interface        //this place iid_idirectdraw2 mentioned in entire solution        hr=directdraw1->queryinterface(iid_idirectdraw2, &temp);        if (failed(hr))           return -1;         _directdraw = (lpdirectdraw2)temp;        directdraw1->release();         /* set default cooperation level */        hr = idirectdraw2_setcooperativelevel(_directdraw, allegro_wnd, ddscl_normal);        if (failed(hr))           return -1;         /* capabilities */        _ddcaps.dwsize = sizeof(_ddcaps);        hr = idirectdraw2_getcaps(_directdraw, &_ddcaps, null);        if (failed(hr)) {           trace("can't driver caps\n");           return -1;        }         _dxhwnd=allegro_wnd;       return 0;     }  

any ideas? why works in 1 solution , not in one? oh linker loathe thee.

did add dxguid.lib project's linker inputs?