.NET Full Framework issue when referencing .NET Standard 1.4 library

If you get an error message when you try to reference your .NET Standard 1.4 library from a .NET full framework app (like .NET 4.6.1) you may see this error message: System.IO.FileLoadException : Could not load file or assembly 'System.Net.Http, Version=4.1.1.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a

The issue is there’s a bug with the System.Net.Http 4.3.0 package.  The fix then is to install System.Net.Http 4.3.1 in your .NET Standard library.  So your csproj should look like this:

<ItemGroup>
    <!-- Add 4.3.1 version explicitly. -->
    <PackageReference Include="System.Net.Http" Version="4.3.1" />
    <!-- Any other packages here. -->
</ItemGroup>

Now you should be good.

There are a lot of threads on GitHub about this on many different repos, but this fix is only in one of those threads and so I thought I’d post this to make it easier for the next person.