I think that's exactly the problem. Your project file contains this:
<ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
<ClCompile>
<WarningLevel>Level3</WarningLevel>
<SDLCheck>true</SDLCheck>
<PreprocessorDefinitions>WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions)</PreprocessorDefinitions>
<ConformanceMode>true</ConformanceMode>
<AdditionalIncludeDirectories>C:\SFML-2.5.1\include</AdditionalIncludeDirectories>
<LanguageStandard>stdcpp17</LanguageStandard>
</ClCompile>
<Link>
<SubSystem>Console</SubSystem>
<GenerateDebugInformation>true</GenerateDebugInformation>
<AdditionalLibraryDirectories>C:\SFML-2.5.1\lib</AdditionalLibraryDirectories>
<AdditionalDependencies>opengl32.lib;sfml-system.lib;sfml-window.lib;sfml-graphics.lib;sfml-main.lib;%(AdditionalDependencies)</AdditionalDependencies>
</Link>
</ItemDefinitionGroup>
For DEBUG it should have
-d in the end (from the documentation):
Here are the dependencies of each module, append the -d as described above if you want to link the SFML debug libraries:
...
link your project to the sfml-main module ("sfml-main-d.lib" in Debug, "sfml-main.lib" in Release),