Hmm, are you linking with dxguid.lib?
I think alot of the IID_* is contained in it.
-ns

ARG! OK that did it. The project now compiles. What a pain. Is this something new with DirectX 7, or perhaps I've never used the GUIDs in this fashion before.

Well thank you very much! See I knew it was a bonehead problem with a simple solution. =)

Just finished putting together some of the basic components in my DirectX library (Much of it comes for various other souces that I've put together), however I'm having a small, but frustrating problem. I upgraded the library to DirectX 7 and started using the DirectDrawCreateEx metod. It compiles fine, but on building the program I get the following error out of VC++:

Linking...
DDObject.obj : error LNK2001: unresolved external symbol _IID_IDirectDraw7
Release/Stars.exe : fatal error LNK1120: 1 unresolved externals

As far as I can tell everything is OK. Why is it upset about this symbol? I've gone through and removed any old versions of the DirectX headers and libraries that were on the machine, but that didn't help (solved some other problems however). Here is the whole line of code:

HRESULT hr = DirectDrawCreateEx(NULL,(LPVOID *)&DDObj,IID_IDirectDraw7,NULL);

Any ideas? I'm sure it is something simple and/or stupid but I'm just not seeing it.

Hey, glad that worked! I know alot of things in 6.0 needed it too (did some directplay work which definately used the GUID's)
It used to be just DirectDrawCreate which didn't ask for a GUID, which maybe is why you didn't need the library before.
-ns