c# - Could not load file or assembly 'System.ValueTuple'

Question

I've got a VS2017 project that compiles to a DLL which is then called by an EXE written by someone else. Both projects target .Net Framework 4.6.2. I rewrote one of my DLL methods to return a tuple and also imported the associated NuGet package. When I compile the project it includes System.ValueTuple.dll in the output directory which is then deployed to other machines where my DLL is loaded and called by the EXE. But when the EXE attempts to call the method that returns a tuple it crashes:

Unexpected Error Could not load file or assembly 'System.ValueTuple, Version=4.0.1.0, Culture=neutral, PublicKeyToken=cc7b13ffcd2ddd51' or one of its dependencies. The system cannot find the file specified.

I'm not understanding why it's not finding the file since it's in the same folder as my DLL. Apparently MS did not include this assembly in .Net Framework 4.6.2.

Note that my DLL is registered in Windows using a machine.config file. I'm guessing that if I also add System.ValueTuple.dll to this file it will work (haven't tried yet and not sure this is the best approach, especially long term.) Is there a better way, besides waiting for 4.6.3 and hoping it includes this assembly?

Answer 1

ok this feels completely wrong but I cut

  <dependentAssembly>
    <assemblyIdentity name="System.ValueTuple" publicKeyToken="cc7b13ffcd2ddd51" culture="neutral" />
    <bindingRedirect oldVersion="0.0.0.0-4.0.3.0" newVersion="4.0.3.0" />
  </dependentAssembly>

This out of my web.config for the main application.

I was really just seeing what happened to see if there was an underlying dependency or something, not expecting it to run. It just carried on working, all the new functions I have added in the last few days still work.