Access global namespace from proxy header - c++

Question

I have a namespace called "access" in project. This is actually used in many places inside the project. Currently I am writing unit test case for this project. I my unit test, the io.h file getting included from the UT frame work. This io file contains c function called "access". So when I tried to include both the io file and one of my project file, I got the re-definition error for "access".
So I tried to use the proxy header for solving the above problem. For proxy header I included the frame work header file in a namespace to avoid re-definition error.
But that frame work file accessing some global namespaces. So I am getting more issues with that. Is there any way to solve the issue without renaming the namespace.
Here is my sample code.
#pragma once
#include "io.h"
#include <iostream>
class Class01
{
public:
Class01(void);
~Class01(void);
void function() {
std::cout<< " Write something";}
};
#pragma once
namespace access
{
class Class02
{
public:
Class02(void);
~Class02(void);
};
}
proxy header
#pragma once
namespace sample
{
#include "Class01.h"
};
#include "Class02.h"
// NamespaceRedef.cpp : Defines the entry point for the console application.
//
#include "stdafx.h"
//#include "Class02.h"
//#include "Class01.h"
#include "proxyHeader.h"
using namespace sample;
int _tmain(int argc, _TCHAR* argv[])
{
return 0;
}
When I compile the code, I got the following error...
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(19): error C2039: 'acosf' : is not a member of '`global namespace''
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(19): error C2873: 'acosf' : symbol cannot be used in a using-declaration
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(19): error C2039: 'asinf' : is not a member of '`global namespace''
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(19): error C2873: 'asinf' : symbol cannot be used in a using-declaration
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(20): error C2039: 'atanf' : is not a member of '`global namespace''
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(20): error C2873: 'atanf' : symbol cannot be used in a using-declaration
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(20): error C2039: 'atan2f' : is not a member of '`global namespace''
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(20): error C2873: 'atan2f' : symbol cannot be used in a using-declaration crosoft visual studio 10.0\vc\include\cmath(20): error C2873: 'atanf' : symbol cannot be used in a using-declaration
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(20): error C2039: 'atan2f' : is not a member of '`global namespace''
1>c:\program files (x86)\microsoft visual studio 10.0\vc\include\cmath(20): error C2873: 'atan2f' : symbol cannot be used in a using-declaration