Visual C++ 2005 and Direct X opening header problem

I have a beginner understanding of another c++ compiler and have decided to try this for learning about 3D.
When the direct sdk is installed and the line

#include<d3d9.h>

is added. I get the error on compile

1>.\main.cpp(8) : fatal error C1083: Cannot open include file: 'd3d10.h': No such file or directory

What am I doing wrong?

[353 byte] By [Dannycanham] at [2007-12-23]
# 1
You're trying to run a Direct3D10 sample in Windows XP. That can never work.
DavidWeller at 2007-8-30 > top of Msdn Tech,Game Technologies: DirectX, XNA, XACT, etc.,Game Technologies: General...
# 2
1>.\main.cpp(8) : fatal error C1083: Cannot open include file: 'd3d9.h': No such file or directory

Sorry that was an error from me trying to link anything I found in that directory. The error should have been as above.

I did eventually get it working by adding the locations to the
VC++ directories.
But that was me guessing. Is there anywhere that explains this? As it seems a rather important part of the install.

Dannycanham at 2007-8-30 > top of Msdn Tech,Game Technologies: DirectX, XNA, XACT, etc.,Game Technologies: General...