When you upgraded your VC++ project to Visual Studio 2013 or later(?), this warning appears. It looks like VS failed to upgrade projects properly.
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='UnicodeDebug|Win32'" Label="Configuration"> <ConfigurationType>Application</ConfigurationType> <PlatformToolset>v120</PlatformToolset> <UseOfMfc>Dynamic</UseOfMfc> <CharacterSet>Unicode</CharacterSet> </PropertyGroup>
It needs to add “<UseDebugLibraries>true</UseDebugLibraries>” to your *.vcxproj file. See the following fixed file. In a Release configuration, it needs to set false of this attribute.
<PropertyGroup Condition="'$(Configuration)|$(Platform)'=='UnicodeDebug|Win32'" Label="Configuration"> <ConfigurationType>Application</ConfigurationType> <PlatformToolset>v120</PlatformToolset> <UseOfMfc>Dynamic</UseOfMfc> <UseDebugLibraries>true</UseDebugLibraries> <CharacterSet>Unicode</CharacterSet> </PropertyGroup>