Having an assembly issue

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C#

Hello Friends,

In my system I installed some NuGet packages, when I tried to compile I got an error message as below:

"The type 'Task' exists in both 'System.Threading, Version=1.0.2856.102, Culture=neutral, PublicKeyToken=31bf3856ad364e35' and 'mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089'


so I removed the "System.Threading" I installed via Nuget, then the new error message is as:

CS0012: The type 'System.Threading.Tasks.Task`1' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Threading, Version=1.0.2856.102, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

Before this I was running on framework 4.5, so I upgraded to 4.5.1 and change my project to 4.5.1, but the error is still the same as the second error.

So, how do I resolve this issue?

Below is the code I am working on

var client = new HttpClient();
   var values = new List<KeyValuePair<string, string>>();
   values.Add(new KeyValuePair<string, string>("task", task));
   values.Add(new KeyValuePair<string, string>("merchant", merchant_id));
   values.Add(new KeyValuePair<string, string>("ref", id));
   // include other fields
   var content = new FormUrlEncodedContent(values);
                    System.Threading.Tasks.Task<httpresponsemessage> t = client.PostAsync("https://myepay.com/api/", content);
                    t.Wait();
                    var response = t.Result;

What I have tried:

I upgraded to 4.5.1 and change my project to 4.5.1

I edited the web.config from:

<system.web>
    <compilation debug="true" targetFramework="4.5.1"/>

To:

<system.web>
    <compilation debug="true" targetFramework="4.5.1">
      <assemblies>
        <add assembly="System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>

UPDATED

I tried further to resolve the issue, I tried the redirecting ask suggested.below is what I did:

Former

<runtime>
    <assemblyBinding appliesTo="v2.0.50727" xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-9.0.0.0" newVersion="9.0.0.0" />
      </dependentAssembly></runtime>

Latter

<runtime>
    <assemblyBinding appliesTo="v2.0.50727" xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" publicKeyToken="30ad4fe6b2a6aeed" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-9.0.0.0" newVersion="9.0.0.0" />
      </dependentAssembly>
    <dependentAssembly>
        <assemblyIdentity name="System.Threading" publicKeyToken="31bf3856ad364e35" culture="neutral" />
             <bindingRedirect oldVersion="4.0.30319.18402" newVersion="1.0.2856.102" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>

still it gives the same error as:

CS0012: The type 'System.Threading.Tasks.Task`1' is defined in an assembly that is not referenced. You must add a reference to assembly 'System.Threading, Version=1.0.2856.102, Culture=neutral, PublicKeyToken=31bf3856ad364e35'.

And again, I installed a NuGet "NuGet Package Management" and it came with many dependencies. could that be the cause or what else is have I done wrong?