Can not create object of DirectorySearcher class with Visual C++ MFC with project reference of System.DirectoryServices.dll

[Alex B]

System.Director yServices.dll file has been added successfully to Visual C++ project through References in Solution Explorer

using namespace System.DirectoryServices;//line 1268
void CClassName::MethodName(){
...
    DirectorySearcher* directorySearcher = new DirectorySearcher();//line 1701
    directorySearcher->Timeout = 60000;//line 1702
...
}

file.cpp(1268): error C2059: syntax error : '.'
file.cpp(1701): error C2061: syntax error : identifier 'DirectorySearcher'
file.cpp(1701): error C2065: 'directorySearcher' : undeclared identifier
file.cpp(1701): error C2065: 'DirectorySearcher' : undeclared identifier
file.cpp(1268): error C2143: syntax error : missing ';' before '.'
file.cpp(1702): error C2228: left of '.Timeout' must have class/struct/union type
        type is ''unknown-type''
file.cpp(1268): error C2871: 'System' : a namespace with this name does not exist
file.cpp(1702): error C3861: 'directorySearcher': identifier not found, even with argument-dependent lookup

By this way I need to set Request Timeout for SOAP WebService