Error including precompiled header - c++

Question

I am writing a code for console application in using Visual studio 2010 on windows 7. I have included the libraries used in this but when I am building the program with header files only it is unable to include "stdafx.h" header file. This is my code.
#include "stdafx.h"
#include "stgetriggersample.h"
int _tmain(int argc, _TCHAR* argv[])
{
return 0;
}
I am getting this error:
error C1189: #error : "include 'stdafx.h' before including this file for PCH"
"stdafx.h" header file is present in my current directory.
Update
The content of "stgetriggersample.h" is
// StGETriggerSample.h : main header file for the PROJECT_NAME application
//
//#include"stdafx.h"
#pragma once
#ifndef __AFXWIN_H__
#include"stdafx.h"
#error "include 'stdafx.h' before including this file for PCH"
#endif
#include "resource.h" // main symbols
// CStGETriggerSampleApp:
// See StGETriggerSample.cpp for the implementation of this class
//
class CStGETriggerSampleApp : public CWinApp
{
public:
CStGETriggerSampleApp();
// Overrides
public:
virtual BOOL InitInstance();
// Implementation
DECLARE_MESSAGE_MAP()
};
extern CStGETriggerSampleApp theApp;
The content of "stdafx.h" is:
// stdafx.h : include file for standard system include files,
// or project specific include files that are used frequently, but
// are changed infrequently
//
#pragma once
#include "targetver.h"
#include <stdio.h>
#include <tchar.h>
// TODO: reference additional headers your program requires here
I tried writing the code with the option Not Using Precompiled Headers but still I get the same error.
How this can be corrected. Thanks

Answer 1

Perhaps you have been trying to fix this so hard, that, in fact, you have broken something. Let's go through proper configuration of pre-compiled headers usage in Visual Studio (I will use options names from VS2012):
Enable usage of PCH: Project Properties -> Configuration Properties -> C/C++ -> Precompiled Headers -> Precompiled Header -> Use (/Yu).
Set name of precompiled header: Project Properties -> Configuration Properties -> C/C++ -> Precompiled Headers -> Precompiled Header File. In your case you should see there standard PCH name (stdafx.h). You may change that if you want.
(In fact, the most important step) Enable PCH generation: Header is not enough. You also need a .cpp file, that is responsible for PCH content generation (since only source files can be compiled). In you case, you have default stdafx.cpp attached to your project. Click it with RMB, then: Configuration Properties -> C/C++ -> Precompiled Headers -> Precompiled Header -> Create (/Yc).
From now on, first non-empty line of every source file attached to your project (including the one from step 3, responsible for PCH generation) should look like this:
#include "PCH_NAME"
Where PCH_NAME is the name of precompiled header set in step 2.
After all these settings are set this way, I would suggest you to:
Clean your solution.
Check in project properties paths of Output Directory and Intermediate Directory. Delete them (I hope they don't contain any code - they shouldn't).
In solution folder (*), you should also see folder with name like: your solution name-cc50b4e6. Delete it.
This will make full reset of your solution (including IntelliSense database etc.). Then, open your project and compile it.
(*) - In your solution folder, by default. If you have valid Fallback Location set, it will be placed there.

Answer 2

In the code:
#ifndef __AFXWIN_H__
#include"stdafx.h"
#error "include 'stdafx.h' before including this file for PCH"
#endif
it looks like StGETriggerSample.h is checking that stdafx.h has been #included by looking for the compile guard macro AFXWIN_H__. However, stdafx.h is not actually defining this guard macro, it's just relying on the statment "#pragma once" to avoid multiple inclusions. So even if stdafx.h has been included, the #error statement will always trigger.
To fix, add the compile guard
#ifndef __STDAFX_H__
#define __STDAFX_H__
// ... yadda yadda yadda...
#endif // __STDAFX_H__
to your stdafx.h. You can remove the #pragma once statement from stdafx.h if you want to, but it's not necessary.
As an aside, your code is also attempting to #include stdafx.h if it hasn't already been included, but then causing the compile error anyways. I'm pretty sure you only want to do one or the other...