Problem building 3.5 on Windows

[Mark Lawrence]

First time in months I've tried building, first time I've ever had a
problem that I can't solve for myself. I'm using Visual C++ 2010 Express.

1>------ Build started: Project: make_versioninfo, Configuration: Debug
Win32 ------
1> make_versioninfo.c
1>..\PC\make_versioninfo.c(1): fatal error C1083: Cannot open include
file: 'stdio.h': No such file or directory
2>------ Build started: Project: kill_python, Configuration: Debug Win32
------
2> kill_python.c
2>C:\Program Files\Microsoft SDKs\Windows\v7.0A\include\windows.h(151):
fatal error C1083: Cannot open include file: 'excpt.h': No such file or
directory
3>------ Build started: Project: make_buildinfo, Configuration: Release
Win32 ------
3> make_buildinfo.c
3>C:\Program Files\Microsoft SDKs\Windows\v7.0A\include\windows.h(151):
fatal error C1083: Cannot open include file: 'excpt.h': No such file or
directory

etc.

What stupid thing have I forgotten, apart from switching to *nix?