I ran into this problem in building AXCsound. My sources resolve it. I cut
and paste below my solution.

Just above where it says "#include  put:

#ifdef AXCSOUND    //    Or whatever...
#define __RPCASYNC_H__
#endif

This prevents rpcasync.h from being scanned; there are definitions in
midisend.c that do the same job.

In general, AXCSound is Gabriel Maldonado's DirectSound 2.1 compiled with
Visual C++ 6.0, plus my ActiveX control code, so you may find other clues in
there.

-----Original Message-----
From: Hans Mikelson 
To: Csound 
Date: Thursday, November 05, 1998 5:02 PM
Subject: Problem Compiling Winsound?


>Hi,
>
>Just bought MSC++ Pro and when I try to compile the canonical winsound I
>get:
>
>Midisend.c
>D:\Program Files\Microsoft Visual Studio\VC98\INCLUDE\rpcasync.h(77) :
error
>C2061: syntax error : identifier 'LPOVERLAPPED'
>D:\Program Files\Microsoft Visual Studio\VC98\INCLUDE\rpcasync.h(78) :
error
>C2059: syntax error : '}'
>D:\Program Files\Microsoft Visual Studio\VC98\INCLUDE\rpcasync.h(86) :
error
>C2040: 'HWND' : 'struct ' differs in levels of indirection from 'struct
>HWND__ *'
>D:\Program Files\Microsoft Visual Studio\VC98\INCLUDE\rpcasync.h(100) :
>error C2059: syntax error : '}'
>
>etc...
>
>D:\Program Files\Microsoft Visual Studio\VC98\INCLUDE\rpcasync.h(170) :
>error C2059: syntax error : ')'
>Modal4.c
>
>Since there does not seem to be any mention of rpcasync in the Csound
source
>code perhaps some configuration setting is incorrect?
>
>Thanks for any help,
>Hans Mikelson
>