There are SDKs to use and files to include and libraries to use and, often, you might end up with problems when compiling your software. Many times it happens when you customize you include folders in Visual Studio.

I bumped into this problem when I shifted to x64 coding and found a solution I decided to add here for those who need it:

How to reset your includes in VS 2005

1. Go to C:\Documents and Settings\%user%\Local Settings\Application Data\Microsoft\VisualStudio\8.0
2. Find this hidden file VCComponents.dat
3. Rename / Delete it

Go back to Tools > Options > Projects and Solutions > VC++ Directories and you will see the includes are back to the defaults. This time keep'em clean!