fatal error LNK1120: 1 unresolved externals

This should be an easy question.

I'm using C++6.0 and DirectX 7.0 with the SDK.

I'm trying to do this:
hRet = DirectDrawCreate(NULL, &pDD, NULL);

and then compile.
I get the following error:
--------------------Configuration: Project - Win32 Debug--------------------
Linking...
ProjectView.obj : error LNK2001: unresolved external symbol _DirectDrawCreate@12
Debug/Project.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.

Project.exe - 2 error(s), 0 warning(s)

What do I do about this? I have found a question with a similer problem and it said that I press alt-f7 and enter some information. I do not however, have this information.

Thanks for the help!
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xersoftAsked:
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fl0ydConnect With a Mentor Commented:
Project->Settings->Link: ddraw.lib guids.lib
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xersoftAuthor Commented:
That did change the error message somewhat. Heres what I got now.

--------------------Configuration: Project - Win32 Debug--------------------
Compiling...
ProjectView.cpp
Linking...
ProjectView.obj : error LNK2001: unresolved external symbol _IID_IDirectDraw4
Debug/Project.exe : fatal error LNK1120: 1 unresolved externals
Error executing link.exe.
Creating browse info file...

Project.exe - 2 error(s), 0 warning(s)

anyideas on this one? And what exactly am I doing in the project settings? Is there away to just make C++ find the stuff it needs when it needs it so I don't have to do this for each project?
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xersoftAuthor Commented:
hmmmm looks like the bad line was
hRet = pDD->QueryInterface(IID_IDirectDraw4, (LPVOID *) & lpDD);

and I don't know what it does, I commented it out and it seems to compile fine. I guess you did answer the question that I asked, Thanks for the help.
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fl0ydCommented:
The line of code
hRet = pDD->QueryInterface(IID_IDirectDraw4, (LPVOID *) & lpDD);
asks your currently retrieved direct draw interface pointer (pDD) whether it also exposes an IDirectDraw4-interface. If so, it is created and a pointer to it is stored in lpDD. In that case hRet is greater than 0, otherwise it is below 0 - you can use
if( SUCCEEDED( hRet ) ) ... or
if( FAILED( hRet ) ) ...
to check for success/failure. I'm not at my machine right now, so I don't have access to DX7-documentation. As far as I know the refiid for direct draw in dx7 is IID_IDirectDraw7 so you shouldn't try to query for v4, unless there is a reason to do so.
The reason for the linker error is that my last post was partially wrong: replace 'guids.lib' by 'dxguid.lib' and you should be fine. Sorry about that...
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